Let me state again -
Forget about the above - I should have simplified this:
After installation of vCenter 5.5 - regardless of how I defined the SSO administration, whether I used simply administrator@vsphere.local, or whether I placed my domain group in the field and checked the box "this is a group" - the RESULTS were exactly the same:
I can log into web client with domain account immediately after installation without modifying anything (why? because I installed vcener with domain account and checked to box to add the domain as an identify source, this is by design), but when using the C# client I can only log in with the administrator@vsphere.local. This doesn't seem like its by design..
What I'm experiencing would indicate that there is a lack of integration pertaining to permissions with v5.5...
Can you confirm this??