Found it, false-positive suspension. I must apologize on this one, my scanner was looking for a particular line of code which is partially different in your install versus the one it was looking for.
What appears to have happened is IPB's license-verification code changed just enough for my scanner to not detect the code as being present, so it killed it. I've updated my scanner to understand both versions of the license code.
The file even tells that it got changed too:
Code:
Last Updated: $LastChangedDate: 2011-05-10
. Wish I had seen that earlier, would've had it detecting it -properly- by now 
Once again I do apologize for the inconvenience here, and I'll do what I can on my end to ensure it doesn't happen again.