From Continental's
website:
* Lounge Access: Platinum members enjoy complimentary access to SkyTeam lounges worldwide when traveling on or connecting to a SkyTeam operated international* flight. Present your same-day ticket for admission.
*Flights between the U.S. (including Hawaii) and the Caribbean do not apply for complimentary lounge access.
On the other hand, I could have sworn that first class passengers flying to/from SJU, including upgraded elites, were entitled to enter the Presidents Club a few years ago. Now, Continental's
website says:
BusinessFirst customers are also welcome to visit the Presidents Club. A BusinessFirst boarding pass is required for admission. BusinessFirst customers can also bring up to two guests, or a spouse and children under the age of 21. Domestic First Class or International Business Class do not qualify for admission.