I already reported this to Gemini, and I know Chris Paterra replied that there will be a patch for this error in the next forum module release, but I need a workaround before this release (date unspecified) related to open posts being submitted after user timeout / logout, which results in a critical error in the forum in which the post was submitted. 

"I discussed with Cathal, I had already handled this but wanted to post a comment so it is confirmed as fixed for 4.4.5."

I'm sure the next version will make it impossible for a user to create a database error after being logged out and give the user notification that they can't submit the post after being timed out or allow the user to save the the post until login, but for now this particular application error results in data loss. If someone knows how this can be fixed short of restoring from the last good backup (also data loss), please let me know. I have no idea when the version that fixes this will be released, so I do need a way to fix it before then. Thanks.

There is vague descirption of a brute force  fix here:

http://www.dotnetnuke.com/Community/Forums/tabid/795/forumid/7/threadid/237978/scope/posts/threadpage/2/Default.aspx

Hi Valery.

Sorry for the late reply.  I didnt see this thread.

You are correct in that I replace the corrupt userID (shows as zero in forum posts table) to the original userID of the poster.  Have had to use this a few times lately and works everytime.

Hope this helps.

Dave