I did a search for 'font' throughout the .java files and found Verdana, Arial, and Helvetica. Also, the chat windows seem to use Times New Roman, perhaps a default? I think picking one or two bit-like typefaces to do all the work would help stylize the overall feel of the game.
Although, them fonts might not include special characters. But I'm sure there are bit type fonts somewhere that do cover the extended alhabits. Regardless, even if we picked Helvetica, I think a dominant typeface should be chosen! xP