Keep your BizTalk Server up to date with the most recent cumulative update package for Biztalk Server 2006 R2 SP1. This package contains all of the Biztalk Server 2006 R2 hotfixes that have been released since the initial release of SP1.
CU#2 KB Article: http://support.microsoft.com/kb/2211420
Previous CU KB Articles:
CU#1 KB Article: