DST Impact on BizTalk Server
With the change in Daylight Saving Time as mandated by the Energy Policy Act 2005, systems running on BizTalk Server 2004 and 2006 may be impacted. Microsoft has published hot fixes for the same. Do review these and apply as applicable.
BizTalk Server 2004 - http://support.microsoft.com/kb/931960
BizTalk Server 2006 - http://support.microsoft.com/kb/931961