Trying to integrate with SourceGear Vault

Howdy.

Tried to set up TeamCity 6.0.3 today and integrate with SourceGear Vault 4.0.6.
I get up to entering the server url and get this error:

"Exception occurred while trying to connect to Vault server. See original message below:
The server uses a protocol that is not supported by this client."

The URL is:

http://<servername>/VaultService

The only posts I can find relating to this, are trying to use SSL...I'm not =/

So any ideas? Or any other info I can supply?

Obviously, I can reach the URL in a browser...

Any help appreciated :)

Thanks!