That was the main reason I wrote gitolite
(http://github.com/sitaramc/gitolite), though now it does a heck of a
lot more than just that.
That's great. You might want to consider making it a deb package
that's available from one of the Ubuntu/Debian repositories. An apt
search on Ubuntu 9.10 doesn't reveal it. I usually shy away from
installing software on my machines that is not automatically managed.
- Mohit