Thank you for a nice theme!
Some minor issues:
- compose message screen: 'Followup-To' is visible by default (as Julius Caesar already pointed out)
- the icons are a little bit too small for my taste
- in the address book, the 3 icons on top are displayed without the border-box around them - this looks inconsistent (compared to the message icons)
- the reload inbox button looks a little bit out of place; it would be better located in front of the other message related icons (like in the default theme) or look better with the border-box around it as well
- the background image on login page is missing (as seen on the screenshots
on your site; maybe on purpose)
- in IE6, the logon box is cut off at the end (see attachment)
@xyanide
There is a button to mark messages (yellow star).