The new file is up now, mojoportal-2-2-6-7-b-mssqlreleasefiles.zip, other db versions to follow soon.
The bug I introduced was pretty bad. The task queue manages tasks on background threads. When I changed the way the tasks are serialized to fix the medium trust issues I introduced a bug in the detection of whether the task manager task is still running, it would come back false so multiple instances of the task were being launched when there should only be one. Each instance is on a new thread so using up threads from the thread pool.
Sorry for the inconvenience of having to upgrade so many times, if its any consolation I'm having to do it too.