looks fine here in IE9, so you probably just need to clean out your IE9 cache.
and if you're using Developer Tools in IE9, make sure you're testing in IE9 mode (not IE8 or IE7 mode).
It's ok from here in IE8 mode, but IE7 mode is a bit wacked. Oh - and IE9 compatibility view is a bit wacked as well.
From a quick glance I'd say that's a result of your #container css stuff.
cheers
Bruce