When I'm doing something that needs admin privileges on my OS X Snow Leopard computer, the prompt shows up and works correctly, but the text is unreadable (some special character is repeated instead of "regular" text):

I'm not allowed to post images yet, but you can see a screenshot of the issue here:
<http://dl.getdropbox.com/u/413086/Screen%20shot%202009-11-15%20at%2010.16.37%20PM.png>

Any ideas on how I might go about fixing this? So far I've tried rebooting, which did nothing.