I've put together a patch that adds Unicode fonts to Kindle 2. I plan to release it publicly after more testing. Since I've tested it in and out on my Kindle 2 as much as possible, I'm looking for volunteers to try it.
Screenshots and details can be found here:
Cyrillic Kindle - Beta testers needed!
If you are interested in testing the patch - either PM me or drop a comment on my blog and I'll email you.