A variant of the split personality syndrome?

When I logged in these forums earlier today, I experienced what I think may be a curious variant of the split personality syndrome. In Firefox 3.6.15 under Mac OS 10.6.6 I used my bookmark to this particular forum. When I came in, the "Welcome Claudio González" next to my new avatar was there as usual below the Forums title. But in the list of threads, there was a recent one initiated by me, in which my avatar was fine, but my name had some garbage added at the end. I therefore opened the thread, and there I appeared with my new avatar, the correct number of my posts and and my correct registration date, but with the same wrong name. I then opened my profile and, to my surprise, there was no photo, no history, no avatar, no recent activity, nothing. Everything was blank.

Suspecting a possible Firefox problem, I closed Firefox without attempting to correct the problem, and moved to my Win 7 machine. On using my bookmark to this forum, I found that everything was completely normal, both in Explorer and Safary. No letters added to my name, my profile was as usual, nothing abnormal at all.

I then came back to my Mac, reloaded Firefox, and used my bookmark to this forum. And everything is back to normal again!