Please consider replacing "Bitstream Vera Sans" font with the equivalent from the DejaVu fonts (http://dejavu-fonts.org). I'm not 100% sure about the naming, but it should be "DejaVu Sans".
From their website: "The DejaVu fonts are a font family based on the Vera Fonts. Its purpose is to provide a wider range of characters while maintaining the original look and feel through the process of collaborative development, under a Free license.".
The original Bitstream Vera fonts are not being maintained any more. The dejavu project has improved the vera fonts, especially for foreign languages. For example the Greek vera glyphs look awful, but in dejavu, they look just fine. The dejavu fonts are shipping with most of the linux distros and are also the default font in most of them. So this is especially important for linux users.