This is another Bulgarian translation, done by myself. I now see there's already a Bulgarian translation in svn, so maybe someone should decide which one is better. This is what I feel it should be, and is complete as of 0.1-beta2. I will soon publish current svn version compatible localization.
Files are at http://mirror.net1.cc/projects/roundcubemail%20-%20bg%20language/
Regards, Doichin