Here is information on running Microsoft CRM 3.0 Mail router on MS Exchange 2007
Links
http://blogs.msdn.com/crm/archive/2007/02/08/crm-and-exchange-2007-download.aspx
http://www.microsoft.com/downloads/details.aspx?FamilyID=f7656f0f-4195-4a7d-b654-2786787e1422&displaylang=en