BizTalk 2006 R2 Beta 2

Go get the BizTalk 2006 R2 Beta 2 bits here:  http://connect.microsoft.com/

There are some known issues documented in the release notes.  Take a look here: 

http://download.microsoft.com/download/8/a/9/8a947a42-4f44-4f9a-886a-2fe48f8ecc6e/BizTalk%20Server%202006%20R2%20Release%20Notes.htm

You will have to apply through the connections link.  It is FREE as long as you have a Passport account.  Also, while you are there, check out Microsoft Game Studios Beta Program and Microsoft Robotics Studio Beta (CTP).