A DigitalPoint Forums thread points to a Google Groups announcement where Google has now included support for Bulgarian and Serbian languages for Google AdSense.
This is good news, especially since I know a few people from both places, despite the fact that some DigitalPoint forums folks feel that nobody speaks either language.
I would be interested to know how many people speak either of those languages.
I assure you, there are people who do.
Forum discussion at DigitalPoint Forums and Google Groups.