What's with the color distortion in WPMU?

Hi everyone - has anyone else observed the color distortion issues in recent WPMU installations? I suspect it's a config problem on my end but I have a virgin install of WPMU at http://www.reictr.com and the colors are being distorted. For example:

* the white background that should be on the default theme doesn't show up
* I switched to a different theme (prosense-blue) and all of the colors were washed out and entirely wrong
* the preview images for the available themes don't show up in the admin area

This problem exists on both IE and firefox. Further, this installation is on the same server where many WP installs exists and work properly.

If anyone has any ideas, I'll be really grateful. Thanks!