Maybe the russian fonts must come from the FirmWare. The original FW doesn't support russian. If you "russify" your reader, it has russian language as option instead of netherlands.
I changed my FW of my 600 as I was missing the clock in the lower right corner and there's the capability of creating screenshots. So I went for the russification and didn't regret it (allthough I now have russian as language option which I cannot read. But I cannot read netherlands either).
But be carefull, all FW-hacks (I would prefer to call them extensions rather than hacks) hold the risk of bricking your hardware if not done correctly.
Here's the original forum:
www.the-ebook.org/forum/index.php
I had used google translate to get to the important notes on what to do, but if you're looking for russian on the reader, you shouldn't have that same problem.