git submodule: 3 modules same git repo?

[Joakim Tjernlund]

I am trying to create 3 submodules from the same git repo, each pointing to a 
different branch.
Since the repo is somewhat large, I don't want the 3 submodules to clone the 
same repo 3
times, I want one clone and then have the 3 submodules to point to different 
commits.

Is this possible? If not, could it be added?

  Jocke