The opinion of the Court was delivered by
Proctor, J.This case concerns the distribution of the proceeds of two federal income tax refund checks totaling $31,284.89. The checks are payable to “Robert and Audrey Hoffman.” Robert is now deceased and his estate is insolvent. The sole assets available for distribution are the proceeds of the checks, and the question before us is the priority of the respective claims to the money made by Robert’s former wife Audrey Hoffman; his accountant Philip B. Brooks; and Robert’s estate.
Robert and Audrey Hoffman were married on Eebru-ary 4, 1954. Audrey was granted a judgment nisi in an action for divorce on October 13, 1965. The judgment granted Audrey custody of the the three children of the marriage and, in lieu of alimony and child support, incorporated a separation agreement entered into- between Audrey and Robert on June 21, 1965.
The agreement provided that Robert would pay $85 per week for Audrey’s support, and $125 per week for the support of the children. The payments to Audrey would cease upon the death of either Robert or Audrey or upon her remarriage; the payments for each child would cease upon attaining the age of twenty-one or upon emancipation. The agreement further provided that Robert would maintain at least $25,000 in life insurance' coverage on his life for each of the three children.
Audrey agreed to rear the children and provide for all other of their expenses not expressly required to be paid by Robert. She also promised to convey all rights to the family home upon Robert’s payment to her of $5,000.
*73Paragraph 17 of the agreement concerned the filing of joint income tax returns.for the years of their marriage:
“Within 5 days after so requested by the husband, the wife shall furnish the husband with all necessary and pertinent information as to her income, expenses and taxable gains and losses for income tax purposes and will sign any joint Federal or state income tax returns and other necessary documents, provided they are not false or fraudulent, for any year or years, including those for the year 1964, during which they shall have been husband and wife. If the wife fails or refuses to do so, all provisions herein for her support and maintenance shall forthwith be of no force and effect. All liabilities on joint income tax returns heretofore and hereafter filed jointly by the parties shall be borne by the husband, who will indemnify and hold the wife harmless from any claim or expense arising out of any such returns, except that the wife shall be liable for taxes on dividends and interest received by her in excess of $500. per year and for taxes on all income earned by her, which taxes shall be computed as if such dividends, interest and income were her only income and she were single. All audits, examinations, suits or other proceedings in connection with those returns shall be handled, at his own cost, and expense, by the husband and by the counsel or the accountant selected by him, but, at the request of the husband, the wife shall participate therein and execute papers to the extent reasonably required by such counsel or such accountant. All refunds recovered with respect to those returns shall belong entirely to the husband, except as to the wife’s separate income, and the wife will promptly sign or endorse any receipts, vouchers or refund checks required to effect the collection of such refunds by the husband.”
Paragraph .20 of the agreement provided:
“The waiver of any individual clause in the within agreement or the failure on the part of either party to insist upon the strict performance of any particular clause or obligation shall not be considered a waiver of the remainder of the said agreement, but the balance of the agreement shall continue in full force and effect.”
On February 9, 1967, Audrey filed a motion in the Chancery Division of the Superior Court to hold Robert in contempt of the 1965 divorce decree. She claimed ar-rearages for her support and the support of her children of $1,050 as of January 28, 1967; she also demanded proof of the existence of the life insurance policies for the benefit of the children and a full account of Robert’s financial *74affairs. On March 30, 1967, Audrey filed another motion for a contempt order, alleging that the arrearages had then reached $2,940. The Chancery Division adjourned both motions without date, noting that defendant apparently was without funds and confined to a hospital for psychiatric care. However, the court directed the attorneys for the parties to confer about Robert’s financial situation. Apparently nothing resulted from this conference, since a subsequent application was filed by Audrey on April 26, 1968, in which she sought to fix her arrearages at $6,007, and asked for permission to serve interrogatories directed to Robert’s financial affairs. In an order filed August 30, 1968, the court denied Audrey’s motion to fix the arrearages and hold Robert in contempt, but granted her leave to serve interrogatories.
Robert Hoffman died on September 30, 1968. After his death, the successor trustee of the Robert Hoffman Chevrolet Employees Profit Sharing and Retirement Plan, a judgment creditor of the decedent, brought an action in the Chancery Division in which the trustee sought a determination of the rights to the proceeds of two federal income tax refund checks. The checks — one for $2,442.85 received June 13, 1967, and one for $28,842.04 received September 30, 1968 ■ — • are both payable to “Robert and Audrey Hoffman,” and were issued as a result of the filing of amended joint tax returns for the years 1964 and 1965. The returns were prepared and filed by Philip Brooks, the accountant for Robert Hoffman. The trustee asked that the checks, which were in the possession of Brooks, be turned over to the court pending further proceedings. The checks had been mailed directly to Brooks, but Audrey refused to endorse the first check and Robert died at about the time of the delivery of the second.
Subsequently, on September 9, 1969, the Chancery Division ordered that Robert’s last will and testament be admitted to probate and that letters testamentary be issued to Gene Hoffman, the decedent’s brother, as executor of *75the estate. The court also directed that the tax refund checks he surrendered to the executor; that the checks be endorsed by the executor and Audrey; and that the proceeds' of the checks be deposited in a trust account pending determination by the court of the claims to the money. No further proceedings were taken in the Chancery Division.
On November 11, 1970, the executor filed a complaint in the Probate Division of the Essex County Court asking that the estate of Robert Hoffman be declared insolvent. According to the account of the estate filed by the executor, the only assets available were $31,284.89, the amount of the two federal income tax refund checks. Total claims against the estate were well in excess of the proceeds of the checks. Among the claims were a balance due of $16,177.43 on a judgment entered July 14, 1967, in favor of the Bank of Passaic and Clifton, and the judgment in the amount of $68,185.81, entered July 22, 1968, in favor of the trustee of the Robert Hoffman Chevrolet Employees Profit Sharing and Retirement Plan.
The court ordered that the proceeds of the checks be distributed according to N. J. S. A. 3A:2A-2.1 The court thus directed that the proceeds be used for payment of the funeral expenses, the administration expenses, and the claim of the Passaic and Clifton Bank, with any remaining funds to go in partial payment of the judgment of the trustee of the Robert Hoffman Chevrolet Employees Profit Sharing *76and Retirement Plan. The court determined that since neither Audrey Hoffman nor Philip Brooks had reduced their claims to money judgments, they were general creditors subordinate to the claims of the judgment creditors.
Audrey Hoffman appealed to the Appellate Division, and Philip Brooks cross-appealed. In an unreported opinion the Appellate Division affirmed substantially for the reasons expressed by the County Court, and we granted certification on the petition of Audrey Hoffman and the cross-petition of Philip Brooks. 62 N. J. 202 (1973).
We deal first with the claim of Philip Brooks. He seeks to collect from the proceeds a fee of $2,275 for his preparation of the revised income tax returns. Ho one disputes the reasonableness of the amount of the fee. According to the affidavit filed by Brooks, sometime in 1966 Robert Hoffman told Brooks that he had been borrowing funds at high interest rates and had been speculating in the stock and commodities markets in the years 1964 and 1965. Brooks then informed Hoffman that income tax refunds might be obtained for 1964 and 1965 if amended returns wére filed in which the interest payments were taken as deductions and the investment losses in the stock and commodity markets were claimed. At the time of this discussion Hoffman was without funds. He asked Brooks to prepare and file amended tax returns and promised to pay Brooks for his services out of the money that would be recovered, if any, in tax refunds. Brooks states that he agreed to do the work “only because of decedent’s promise to pay me out of the proceeds of any income tax refunds that would be received.” Brooks had arranged with Hoffman that any tax refund cheeks would be delivered directly to Brooks.
The trial court held that since Brooks had not obtained a judgment against Hoffman his claim was simply that of a general creditor, and therefore it was subordinate to those preferred claims under N. J. S. A. 3A:2A-2. We believe the trial court misconstrued Brooks’ position. Brooks does not raise his claim under N. J. S. A. 3A:24-2. Rather, he *77argues that the refund proceeds are subject to- an equitable .lien in his favor which attached to the money before the statute is applied.
An equitable lien “may be created by express executory contracts relating to specific property then existing, or property to be afterward acquired; and sometimes they are raised ex aequo et bono, according to the dictates of equity and conscience, as where a contract of reimbursement could be implied at law . . Temple v. Clinton Trust Company, 1 N. J. 219, 226 (1948). See also In re Loring, 62 N. J. 336, 341 (1973). Such a lien is a right of a special nature in a fund and constitutes a charge or encumbrance upon the fund. See 4 Pomeroy, Equity Jurisprudence (5th ed. 1941) § 1233, p. 692; 51 Am. Jur. 2d, Liens, § 22, p. 160. Where one promises to pay for services rendered out of a fund created in whole or in part by the efforts of the promisee, a lien in favor of the promisee will attach to the fund when it comes into existence. See Morrison Flying Service v. Doming Nat’l Bank, 404 F. 2d 856, 861 (10th Cir. 1968), cert. den. 393 U. S. 1020, 89 S. Ct. 628, 21 L. Ed. 2d 565 (1969); Mitchell v. Bowman, 123 F. 2d 445, 447 (10th Cir. 1941). In Rutherford Nat’l Bank v. H. R. Bogle & Co., 114 N. J. Eq. 571 (Ch. 1933), the court described the creation of an equitable lien:
“The whole doctrine of equitable liens or mortgages is founded up.on that cardinal maxim of equity which regards as done that which has been agreed to be, and ought to have been, done. To dedicate property, or to agree to do so, to a particular purpose or debt is regarded in equity as creating an equitable lien thereon in favor of him for whom such dedication is made. This wholesome equitable principle is one of wide, if not universal, recognition and application [citations omitted].
“The form which an agreement shall take in order to create an equitable lien or mortgage is quite immaterial, for equity looks at the final intent and purpose rather than at the form. If an intent to give, charge, or pledge property, real or personal, as security for an obligation appears, and the property or thing intended to be given, charged, or pledged is sufficiently described or identified, then the equitable lien or mortgage will follow as of course [citations omitted].” 114 N. J. Eq. at 573-574.
*78In Wardman v. Leopold, 66 App. D. C. 111, 85 F. 2d 277 (1936), cert. den. 299 U. S. 570, 57 S. Ct. 33, 81 L. Ed. 420 (1936), tax accountants were allowed an equitable lien on the proceeds of tax refund checks which their efforts obtained for a client. The court found that the agreement between the parties contemplated that the fees for the accountants’ services should be satisfied out of the proceeds of the refund, and that consequently the sum due the accountants constituted a charge enforceable as an equitable lien on the fax refund. See also Barnes v. Alexander, 232 U. S. 117, 34 S. Ct. 276, 58 L. Ed. 530 (1914) (attorneys’ contingent fee satisfied out of fund obtained through their efforts).
None of the parties has disputed that Robert Hoffman intended to pay the fee of Brooks from the amount received through the tax refund. Since the fund was created by the efforts of Brooks, we think that his claim falls within the definition of an equitable lien. Accordingly, before others receive the benefit of his efforts, equity requires that Brooks’ claim be satisfied. See 2 Pomeroy, Equity Jurisprudence, supra, § 685, p. 948. See also Rutherford Nat’l Bank v. H. R. Bogle & Co., suprra, 114 N. J. Eq. at 578-579. We thus conclude that the claim of Brooks should be satisfied first from the proceeds of the checks.
Audrey Hoffman’s claim to the proceeds of the cheeks was also determined by the courts below to be simply that of a general creditor. Two reasons were given for this result. First, the trial court said that Paragraph 20 of the property settlement agreement “specifically states that a failure of either party to perform any part of the agreement does not mean that the balance of the agreement is inoperative or ineffective,” and it thus concluded that a breach by Robert would not release Audrey from her promise to endorse the checks and recognize his sole ownership of the proceeds. However, we think that the court misconstrued this paragraph. This provision was not intended to make each party’s promises under the agreement independent of *79the other’s performance, but rather was designed to permit one party to waive enforcement of certain obligations under the agreement without precluding that party from enforcing the remainder of the agreement. In the present situation, this provision therefore does not bar Audrey from raising Robert’s breach of the agreement as releasing her from her promise with respect to the tax refunds.
The second reason given by the trial court to subordinate Audrey’s claim was that Robert’s alleged breach of the agreement had not been reduced to a money judgment by Audrey, and consequently her claim was only that of a general creditor subject to the claims accorded priority in N. J. S. A. 3A:24-2. In her brief on appeal, Audrey concedes that “the award of alimony and support possesses the force of a judgment at law only in those cases where the court has certified the amount thereof.” nevertheless, she argues that although her arrearages were never fixed by the court, her right to the proceeds of the checks is not dependent upon her position as a judgment creditor. Rather, she contends she is entitled to the proceeds before they become assets of the estate and sirbject to distribution under N. J. S. A. 3A:24-2.
Audrey first claims that she is a joint tenant, and thus entitled to the full amount of the proceeds of the checks. She cites Ehrlich v. Mulligan 104 N. J. L. 375 (E. & A. 1928), where it was held that there was a right of survivorship in a note payable jointly to husband and wife. However, in the present case Robert and Audrey were divorced at the time the checks were issued. They were not designated as joint tenants in either cheek. Therefore, no right of survivorship was created, and we accordingly reject Audrey’s claim to take the money as Robert’s survivor.
Audrey next contends that if she is not a joint tenant, she nonetheless had a legal right to one half of the proceeds as a tenant in common. In opposition to her claim, the executor relies on Paragraph 17 of the agreement in which Audrey declared that she would endorse the checks and that all of *80the proceeds would belong to Robert. The executor argues that by this provision she gave up whatever legal interest she had in the proceeds.
While it is true that in the separation agreement Audrey promised to endorse the checks and convey whatever legal interest she retained to Robert, we believe that her covenant to endorse the checks cannot be viewed as independent of Robert’s performance of his obligations under the agreement. The checks were payable to “Robert and Audrey Hoffman,” and Audrey’s endorsement was required before the checks could be negotiated. See N. J. S. A. 12A:3-116. In Woodhouse v. Woodhouse, 15 N. J. 550 (1954) this Court refused to hold a wife to the promises she made in an agreement because the husband failed to perform his promises in the agreement. The property settlement agreement in that case allowed a credit against the husband’s support payments to the wife if she received income from any other source. When the husband failed to meet his payments, the wife found it necessary to get a job. We rejected the husband’s contention that her employment income should be credited to his support payments, stating that “[sjalutary principles of justice inhibit the enforcement of a promise when the counter-promise has been broken.” 15 N. J. at 556.
As in Woodhouse, in the present case we think that Audrey’s promise to endorse the checks was dependent on Robert’s performance of his obligations under the agreement, and that the parties would not have intended that Audrey would have been forced to perform when Robert was unable or unwilling to fulfill his own obligations to Audrey and the children.
Although there is no proof in this case establishing to what extent the refund proceeds represent respective over-payments or losses of either spouse, it is clear to us that Robert believed that Audrey’s cooperation in filing a joint return would be of considerable value to him. Robert sought to insure that Audrey would cooperate in the filing of the *81returns by including a specific provision in the agreement to that effect. It should also be noted that the penalty imposed on Audrey for her failure to perform her covenant in Paragraph 17 to provide information concerning her individual income and deductions was that all provisions for her support and maintenance would be of “no force and effect." The severity of this penalty indicates that Robert viewed Audrey’s performance as of significant importance to him. Moreover, the fact that Audrey’s cooperation in filing the joint return was expressly linked with her right to support suggests to us that the parties viewed the obligations undertaken by Audrey in Paragraph 17 as connected with Robert’s obligations of support and maintenance. Under these circumstances, we think that a fair interpretation of the intent of the parties was that Audrey’s performance of her obligations in Paragraph 17 was not a simple formality, and that the parties themselves would not have viewed Audrey’s performance as independent of Robert’s responsibilities.
If Robert had sought to enforce Audrey’s promise in Paragraph 17 while he was alive, he would have had to obtain an equitable order directing her specific performance. But it is well established that one who has either broken a promise in some material respect or is unable substantially to perform his own obligations under an agreement cannot get a decree for specific performance. See 5A Corbin, Contracts, § 1175, pp. 301-302, § 1183, p. 339 (1964); 11 Williston, Contracts, § 1425, p. 831 (3rd ed. 1968) Restatement, Contracts § 373. In view of Robert’s failure to perform, we think that equity requires a constructive trust be imposed on the proceeds of the checks. See D’Ippolito, et al. v. Castoro, 51 N. J. 584 (1968); Scott, Trusts, § 462, p. 3413 (3rd ed. 1967). We think it would be unjust to permit Robert’s estate to retain the full proceeds of the tax refunds when Robert did not fulfill his promises to Audrey and the children in the separation agreement. The refunds were obtained with the cooperation of Audrey, and we believe she should not be compelled to re*82linquish her interest in the refunds without some protection of the rights she and the children have under the separation agreement.
While we believe that Audrey retained an equitable interest in the proceeds, we also recognize that it is difficult to determine the exact extent of that interest. In light of Robert’s illness and his changed financial circumstances, a court of equity could have determined that Robert’s obligations in the agreement should have been modified to reflect his ability to pay with consideration for his financial obligations to others. See Schlemm, v. Schlemm, 31 N. J. 557, 580 (1960); Flicker v. Chenitz, 55 N. J. Super. 273 (App. Div. 1959), appeal dismissed by consent, 30 N. J. 152 (1959). Under the circumstances we think the fairest result in order to protect the rights of Audrey and the children with due regard to the interests of the other claimants is to divide the proceeds of the checks according to the legal interests of Audrey and Robert as they appear on the face of the cheeks. Accordingly, after the satisfaction of the claim of Brooks, we hold that the proceeds of the checks shall be apportioned equally between Audrey and the estate of Robert.
We do not think our result prejudices the justifiable interests of any of the parties entitled to priority under N. J. S. A. 3A:24— 2. The statute applies only to the property owned by the decedent. Robert would not have been able to realize the proceeds of the refunds unless Audrey performed her obligations, and consequently her equitable interest in those proceeds attached to the fund before it passed into Robert’s estate. See Clapp, 7 New Jersey Practice, Wills and Administration, § 1280.
We hold that Philip Brooks’ fee should be first satisfied from the proceeds of the refund checks. The remainder of the fund should be divided evenly between Audrey and the estate of Robert Hoffman. The estate’s share of the proceeds should be distributed in accordance with the order of priority provided in N. J. S. A. 3A:24-2, and the case *83is remanded to the trial court for further proceedings consistent with this opinion.
N. J. S. A. 3A :24r-2 provides:
“The following expenses and debts shall have preference and be paid out of the personal and real estate of the decedent, according to the following order:
1. Funeral expenses.
2. Administration expenses.
3. Debts entitled to a preference under the laws of the United States.
4. Hospital, physicians’ and nurses’ bills during the last illness.
5. Judgments entered against the deceased according to the priority of their entries respectively.
Preference shall not be given to the payment of one item over other items of the same paragraph except as stated in paragraph 5.”