We intend to release a patch for this and a few other reported bugs within the next day or two (We need to complete testing on it). Note that this is an extremely difficult exploit to achieve. It requires a user to follow a link posted by someone else to "Send a PM" with some HTML entities within the query string and then (I believe) to hit submit at least once. I would hope that the chances of anyone falling for such a exploit would be extremely low indeed!
