/Topic.xhtml I created a topic. I then went to the topic using the quick search box at the top of the screen. I then edited the topic. I got the angry Terminator. I punched in the topic number to the quick search box. I then arrived at the topic. My changes had been saved, but my original topic text was gone, and the drop-down box showed me one revision only. So my original topic text was lost. Didn't have a revision created for it by the look of it.
I clicked on "Edit Latest Version" The topic opened with my original text in it. I made the change again, then saved it. This time a revision was created. It appears that it was not persisted on the first edit, and although the new text was displayed in the interface, the old text was the text in the database. It's topic 12095.
This is an issue with how seam works when a transaction fails (from my knowledge). Essentially it keeps the Java Bean as it was before the failure and disconnects from the Persistence Context (as normally happens when a transaction is rolled back). I'm fairly sure that the error message indicates that you should relog, I'll double check that though.
Fixed in build 20121123-1253. I've updated all error messages I could find. I also found an issue where the seam conversation wouldn't end when some Exceptions occurred. This was more then likely what was causing the main issue as if the conversation remains active it'll try to use the database connection that has been rolled back and disconnected.