I been having some problems with users registering bogus accounts on my forum. Others have reported the same, this and the shout server was the last mod installed prior to the problem arrising. Not saying that someone exploiting the program, this is a great hack and it is killing me not having in the forum. Since I removed them both I have not had any more problems.
If you are familiar with php my admin look for users born in january 1 1980. All my bogus accounts had that birth date.
If you have access to the apache logs look for
//register.php
For some reason that always shows when they send the create command.
If you find some of those things on your logs then go here and report it;
http://www.vbulletin.com/forum/showthread.php?t=199401
I know this is not fair to this great mod and I am not saying that it is the culprit. Just doing a process of elimination and starting from the last mods I installled prior to the problem.