912945 versus Outlook Web Access...
Yes, I know, we seem to be talking an awful lot lately about IE, Windows and OE patches and the problems they are causing - what can I say - its been a bad month.
MS has released a KB article addressing problems that users of Outlook Web Access may experience after installing the EOLAS patch (aka 912945) as well as problems experienced by users of Windows Vista
http://support.microsoft.com/default.aspx?scid=kb;en-us;911829
Thankfully there is a hotfix available - far preferable to uninstalling the patch.