Teamcity: Invoke build from labelled verison from TFS.

I would like to extend this question. How do you build different branches? we use three branches: DEV, Integration and Release. it is possible to create VCS roots for each of these branches and each time we shift from DEV to Int or from Int to Release edit build configuration and change the VCS but this way is somewhat cumbersome and definitelly not elegant.
Building labeled version is important too when you deliver patches for old verions.