In the 2.2 release I added handling to convert dates to the user's timezone. Unfortunately I introduced a bug. In the Forums the MostRecentPostDate is null when you create a new forum because there are no posts yet. I forgot to include handling for null dates in the Forum module when doing the conversion to the user's timezone so when creating new forums the page containing the forum would throw an exception. Since this pretty much made the forum unusable I considered it a significant bug worthy of an immediate fix.
I also fixed an issue when using mojoPortal with Active Directory. This fix required a new column LdapDomain added to the mp_Sites table so I've added an upgradefrom2-2to2-2-1.sql script for each of the data layers. If using MS SQL or PostgreSQL you'll also need to run the stored procedure script. As always be sure and back up everything before doing an upgrade and post in the forums if you run into any problems.