Strange OS and encodings issue

So, for a very long time i was using OpenfireGatewaySpark for my ICQ account. It was with Win2000 SP4. I had Russian Reg.Settings. Never have changed encoding settings in Gateway. So it was default - iso-8859-1. And i was chatting on russian with my friends. Everything was fine. Now i have switched to XP SP2. All programs are the same. I have copied my old Spark profile. But now all incoming russian messages became unreadable. And in old history i can only read my outcoming messages. All incoming russian messages are converted to some symbols. Finally i have changed encoding settings of Gateway to windows-1257 and now i can read incoming messages normally. But my old history is lost. So, i’m now wondering what was the cause? Was it Win2000 encoding something in such way that XP cant read? Or was it Spark or Gateway?

That’s a really good question. Which OS changed? The one running Openfire or the one where you are running Spark or both? Wasn’t XP when they officially embraced unicode?

Both were on Win2000. Then i switched to XP, installed same versions and copied Openfire’s old db and Spark’s old profile.

I don’t really have any idea. =/ Anyone else seen anything like this?