Configure Designer to work with multiple Repositories

I am currently building out our QA environment for v9.1; our Development environment has been in place for months.

I'd like QA to be able to connect to the DV repository so we can retrieve solutions from DV to deploy to QA.  (I will do something similar on Production to access QA when we build out that environment.)  Each server is on a different network domain.

I added the DEV deployment service entry as a second entry to ...\IIS extensions\DelplymentServiceConfig.xml in QA.

It shows up in the Designer under repositories.  When trying to access, I was getting the "The server has rejected the client credentials." error, so did the steps under section 3.1.4 of the v9.1 documentation "Deploying processes across domains or workgroups".  I set up the DV user/password (the same as the engine account) on the QA server.

Now I am getting "The socket connection was aborted.  This could be caused by an error processing your message or a receive timeout being exceeded by the remote host, or an underlying network resource issue.  Local socket timeout was '00:10:00'.."

I don't see any obvious message on the QA or DV server to give more details.  Am I missing something to be able to access the repository in another level?  (Windows Server 2008 R2; IIS 7.5; SQL Server 2008 R2)