Today I found an excellent post about BizTalk Protocol transition by Paolo Salvatori.
It's absolutely worth reading if you have to work with Webservices / Single Sign On.
He covers 3 scenarios:
Scenario 1 – Messaging Only Scenario with a SOAP Receive Location
Scenario 2 – Messaging Only Scenario with a WCF-Custom Receive Location
Scenario 3 – Orchestration with an Inline Send Port
Have a read of the post >>Here<<