This is an appeal from an Order granting appellee’s preliminary objections in the nature of a motion to strike appellant’s joinder complaint. As appellant Trexler-Haines Gas, Inc. (hereinafter Trexler) followed proper procedure in joining Sun Gas Company (hereinafter Sun), Atlantic Rich-field, John P. Clarke, Co., and Charles A. Hones, Inc. as additional defendants, we hold that the trial court erred in dismissing appellant’s complaint joining those defendants. Accordingly, we reverse and remand.
The facts giving rise to this appeal are simply stated. Appellee Barbara Sherry instituted a personal injury suit against Trexler on September 22, 1983. Trexler filed its answer and new matter on October 26,1983. Moreover, on November 10, 1983 Trexler filed a joinder complaint against additional defendants Sun, Atlantic Richfield Co. and John P. Clarke Co. Service was effectuated on Atlantic Richfield Co. and John P. Clarke Co.;1 however, on February 26,1984 the complaint to join Sun was returned by the sheriff of Montgomery County marked “not found.”
Trexler eventually filed a praecipe on May 28, 1986 to reissue the complaint against Sun. Service of the complaint was made on June 20, 1986. Sun filed, on July 15, 1986, preliminary objections in the nature of a motion to dismiss the complaint on grounds of untimely joinder. A hearing on the motion was held on November 3, 1986. The trial court, on December 16, 1986, ordered dismissal of the joinder complaint against Sun on the basis of untimely service, citing as authority the rescinded Pa.R.C.P. 2254. Trexler timely appealed this order to our Court. Its sole *333contention on appeal is that the trial court erred in applying the rescinded Rule 2254 to the procedures in this case.
I.
Initially we note that joinder of an additional defendant is accomplished by the filing of either a praecipe for a writ or a complaint within sixty (60) days of receipt of the plaintiffs complaint. Pa.R.C.P. 2252, 2253.2 Herein, Trexler filed its joinder complaint within the applicable sixty (60) day time period but did not effectuate proper service upon Sun for over two years.3 Personal jurisdiction over Sun was therefore not acquired during that period.
When Sun was served with the reissued complaint, Sun filed preliminary objections on July 15, 1986. These preliminary objections were in the nature of a motion to dismiss Trexler’s complaint due to late joinder of the additional defendants. However, as stated previously, the record reveals that the joinder of additional defendants Sun, Atlantic Richfield, and John P. Clarke Co. was timely, as it was accomplished within sixty (60) days of appellant Trex*334ler’s receipt of the plaintiffs complaint. Nonetheless, rather than ruling on Sun’s preliminary objections regarding joinder, the trial court, sua sponte, entered an order striking the complaint on the basis of untimely service rather than untimely joinder. This was error.
Undeniably, a trial court may address sua sponte issues of whether jurisdiction is proper. Cheng v. Cheng, 347 Pa.Super. 515, 500 A.2d 1175 (1985); Commonwealth, Dept. of Transp., Bureau of Traffic Safety v. Forte, 29 Pa. Cmwlth. 415, 371 A.2d 526 (1977); Pa.R.C.P. 1032(2). However, here the trial court raised sua sponte the issue of the timeliness of service, a procedural question not addressed by either party. This, we find to be improper. See e.g. Luitweiler v. Northchester Corp., 456 Pa. 530, 319 A.2d 899 (1974) (court cannot sustain a demurrer where no demurrer is made by a party); Galdo v. First Pennsylvania Bank, 250 Pa.Super. 385, 378 A.2d 990 (1977) (court erred in sustaining preliminary objections as to both defendants where only one defendant filed preliminary objections).
Moreover, when a party fails to raise the issue of defective service, that party is deemed to have waived that issue and to have validated an otherwise defective form of service. Cox v. Hott, 246 Pa.Super. 445, 371 A.2d 921 (1977). As Sun failed to plead defects in service, Sun effectively validated that service and should be held to have waived the right to argue that issue on appeal. In this regard, the trial court erred, and accordingly, we must revérse.
II.
Additionally, we hold that the trial court erred in applying the rescinded Pa.R.C.P. 2254 to this case.
Our Supreme Court adopted Rule of Civil Procedure 425, governing the joinder of additional defendants, on June 20, 1985, to be effective January 1, 1986. The rule states in pertinent part:
Rule 425. Additional Defendants
(a) Original process shall be served upon an additional defendant who is not already a party to the action in the *335same manner as if he were an original defendant. Copies of all pleadings filed in the action shall be served with the complaint against the additional defendant.
Note: ...
See Rule 213(b) for the right of an additional defendant to move for a severance and Rule 1006(d) for the right to move for a change of venue.
Rule 401 applies to the manner in which process is to be served upon original defendants:
Rule 401. Time for Service, Reissuance, Reinstatement and Substitution of Original Process. Copies for Service
(a) Original process shall be served within the Commonwealth within thirty days after the issuance of the writ or the filing of the complaint.
(b) (1) If service within the Commonwealth is not made within the time prescribed by subdivision (a) of this rule or outside the Commonwealth within the time prescribed by Rule 404, the prothonotary upon praecipe and upon presentation of the original process, shall continue its validity by reissuing the writ or reinstating the complaint, by writing thereon ‘reissued’ in the case of a writ or ‘reinstated’ in the case of a complaint.
(2) A writ may be reissued or a complaint reinstated at any time and any number of times. A new party defendant may be named in a reissued writ or a reinstated complaint.
(4) A reissued, reinstated or substituted writ or complaint shall be served within the applicable time prescribed by subdivision (a) of this rule or by Rule 404 after reissuance, reinstatement or substitution.
(Emphasis added). These rules replaced the repealed Rule 2254(b) which stated in pertinent part that:
(b) the writ, or the complaint of the defendant or the additional defendant if the joinder is commenced by com*336plaint or the complaint is used as alternative process as provided by rule 1010(e), shall be served by the sheriff in the same manner as a writ of summons within thirty (30) days after the commencement of the action to join, unless the time be extended by the court upon cause shown.
(Emphasis added). Thus, our Supreme Court dispensed with the requirement of the rescinded Pa.R.C.P. 2254(b) that a party must show cause to the court before an extension of time for service be granted. Under the new rules, all that is required for extension of time for service is that the prothonotary reissue the writ or reinstate the complaint before service is again attempted. We note in particular that the new rule states a timely filed joinder pleading continues to be valid after the original time for service has expired as long as the prothonotary reissues the pleading. Pa.R.C.P. 401(b)(1).
The language of the new rules is unambiguous; the requirement that the court exercise its discretion in granting an extension of time for service, and the requirement that a party show cause for such extension, have been omitted. As the language is unambiguous, this Court may not disregard the clear letter of the rules under the pretext of pursuing its alleged spirit. Lamp v. Heyman, supra, 469 Pa. 465, 366 A.2d at 886 (the language of the Rules of Civil Procedure “does not admit of qualification in an effort to ascertain its spirit”).
Appellant contends that the trial court erred in applying Pa.R.C.P. 2254(b) to the service which was perfected after January 1, 1986. We agree. Pa.R.C.P. 52 provides guidance for this issue, as it states:
Rule 52. Effective Date. Application to Pending Actions
(a) A rule or an amendment to a rule shall be effective upon the date specified by the Supreme Court.
(b) If no effective date is specified, the rule or amendment shall be effective on the first day of July or January *337following the thirtieth day after its adoption, whichever is earlier.
(c) Unless the Supreme Court specifies otherwise, a rule or an amendment to a rule shall apply to actions pending on the effective date.
Rescinded and new rule adopted April 5, 1982, effective July 1, 1982.
(Emphasis added).
As the action herein was still pending on the effective dates of Pa.R.C.P. 52, Pa.R.C.P. 401 and Pa.R.C.P. 425, we hold that the new rules, rather than the rescinded Pa.R.C.P. 2254(b), apply. Accordingly, the trial court erred in applying the rescinded rule rather than the current.
The only remaining question, then, is whether appellant properly followed the procedure of Pa.R.C.P. 401 and Pa.R.C.P. 425. Our examination of the record indicates that the complaint was properly reinstated on May 28, 1986 before appellant served Sun on June 20, 1986. Thus, appellant properly served Sun and should be entitled to continue with the action.
We recognize that the result in the instant case may seem anomalous in that, from February 1984 when the sheriff marked on the service forms “not found” until May 1986, appellant made no attempt to comply with the then-in-effect Rule 2254(b) to effectuate service. However, we are reassured by the fact that any inequity resulting from the delay in obtaining personal jurisdiction over Sun can be redressed through various options which remain available to Sun, including: filing a motion to dismiss the complaint, rather than preliminary objections {see Pa.R.C.P. 1017) (preliminary objections limited to, inter alia, questioning service)', filing a motion for extension of time in order to conduct discovery (see Pa.R.C.P. 216, 4007.3); cf. Cohen v. International Organization Masters, Mates and Pilots, Intern. Marine Division of ILA, AFL-CIO, 247 Pa.Super. 83, 371 A.2d 1337 (1977); or filing a motion to sever {see Pa.R.C.P. 213(b)).
*338CONCLUSION
Accordingly, as appellant followed the applicable rules of procedure, we reverse the order of the trial court dismissing appellant’s joinder complaint, and remand for further proceedings not inconsistent with this opinion. Jurisdiction relinquished.
MONTEMURO, J., files dissenting opinion.. Praecipe to join additional defendant Charles A. Hones, Inc. was filed January 11, 1984.
. The dissent contends that joinder does not occur until service of the complaint has been effected. (Dissent at 345). In support, the dissent cites Bandes v. Klimoski, 260 Pa.Super. 137, 393 A.2d 1050 (1978). We find this case inapposite. In Bandes this Court noted that while "the joinder itself was timely accomplished’ by filing a praecipe for a writ within sixty (60) days, dismissal of the complaint of joinder was justified because service was not made within the applicable thirty (30) day time. Bandes, supra 393 A.2d at 1052. (Emphasis added). We find no authority in the clear language of the rules, nor in prior caselaw for the proposition that joinder is not accomplished until service is made. Accord Bandes, supra. See also Scabis v. Nobel, 63 D & C 52 (1947); discussion Section II, infra. Rather, we conclude the dissent has confused the separate concepts of joinder and service as did the trial court. Furthermore, any reliance on Pennsylvania Standard Practice for this proposition is misplaced as that treatise concludes personal jurisdiction over an additional defendant is obtained through service rather than through filing the joinder pleadings. As Sun was legally served, pursuant to the new applicable rules, personal jurisdiction over Sun was obtained. However, joinder was accomplished when the pleadings were filed.
. Trexler was served with the complaint on September 22, 1983 and, in turn, filed its complaint joining the additional defendants on November 10, 1983.