Thank you for reporting this. We'll try to take care of the bug as soon as possible. The bug is reproducible in Firefox 3 / Mac OS X as well, and I'm 99% sure that's a coding bug on the new system.
The system is kinda new and was made specifically for ZD, so a few bugs exist. We ask you (the users) to be a little patient as there's a lot to do to get this site up-to-date.