cant connect to repository in VS2008

I have a repository created on a separate server to the VS projects, however when I receive an invitation it is of the form;

teamRepository=https://localhost:9443/jazz
userId=geoff
userName=geoff
projectAreaName=OPCTest

When I run "Accept Team Invitation" from the VS IDE Client, I am replacing the localhost with the actual server name (tusk_sql1), however when I try to create a repository connection the login always fails. I can access the server in a browser from this machine using https://tusk_sql1:9443/jazz/admin, and I can login with the username/password so I know the connection and authentication is ok.

I get a Logon failed window with the message, "failed to contact the repository geoff@tusk_sql1", which does not make sense as that is the username?

I have also tried manually creating the repository connection, and it always fails to login.

Is there anything that I need to configure on the server to make this visible to VS IDE?