Exchange Team has release a new rollup for Exchange 2010 SP1. this is the 5th rollup since Exchange 2010 SP1 was released. You can find below essentials links for more information about this rollup.
Description of Update Rollup 5
http://support.microsoft.com/kb/2582113
Download link for Update rollup 5
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=27193