Today I troubleshooted an issue on Exchange 2010.
When the users clicked the Options button to access the Exchange Control Panel, the OWA page just reloaded and nothing happend.
Also when I tried to access the url for the ECP https://url/ECP I came to the OWA page.
One configuration change we did to remove the timezone and language prompt for our OWA users, was to set the defaultclientlanguage on the OWAVirtualdirectory.
When the OWAvirtualdirectory -defaultclientlanguage is set to something else than 0, this issue will occure.
I have now send a bug report to Microsoft, to find out if this is by design, or if its a bug.