CS2 licensing question

When I bought the student/teacher edition of CS2 (PC), I got 3 licenses. I now want to use an extra license for my student. Where do I check into the validity of doing that? I also have CS5 that I use- when I registered that, it didn't cancel out my CS2 status, did it? I use that version for my plugins. I cannot find the Adobe ph# that I used to call.