Today, Microsoft released the first Update Rollup for Service Pack 2.

This update rollup contains a lot of updates, amongst also the following:

• New updates for Dec DST - Exchange 2010 - SP2 RU1 - Display name for OWA.
• 2616230 Exchange 2010 CAS server treats UTF-7 encoding NAMESPACE string from CHS Exchange 2003 BE server as ASCII, caused IMAP client fails to login.
• 2599663 RCA crashes when recipient data is stored in bad format.
• 2492082 Freebusy publish to Public Folders fails with 8207 event.
• 2666233 Manage hybrid configuration wizard won't accept domains starting with a numeral for FOPE outbound connector FQDN.
• 2557323 "UseLocalReplicaForFreeBusy" functionality needed in Exchange 2010.
• 2621266 Exchange 2010 Mailbox Databases not reclaiming space.
• 2543850 Exchange 2010 GAL based Outlook rule not filtering emails correctly.

Update 2666233 relates to an issue that I reported earlier in the following article: 

• http://www.pro-exchange.be/blogs/exchange2010/archive/2012/01/24/hybrid-configuration-wizard-fails-when-using-a-wildcard-certificate.aspx

Furthermore, this UR also includes update 2579051, which relates to an error that was described in the following article: 

• http://www.pro-exchange.be/blogs/exchange2010/archive/2012/01/13/exchange-2010-sp1-moverequest-fails-with-mapiexceptionnosupport.aspx

For more information and a full overview of the included updates, have a look here