When trying to create a new thread in the Chatter forum, the category dropdown list is not updating properly after the forum is selected/changed. As a result it's not possible to select a correct category for the chosen forum; when you try to save your message you get:

"The category selected does not match the forum selected. This is due when a connection problem occured during the transmission when you access the new message form. Please, copy your message so it will be saved in the clipboard and click again on the new message icon in order to make sure that it loads properly. Then, you will be able to paste your text as is."

For example, my default forum is Visual FoxPro. If I change the forum of a new message to Chatter, the dropdown list for Category remains on the Visual FoxPro categories rather than updating to the Chatter categories.

This message is in the Visual FoxPro forum because I can't get it into the Chatter/UT-related forum/category :-/