git diff looping?

Running Git 1.6.1 on Solaris 10, git diff seems to go into a loop -
consuming CPU and producing no output after a little bit.  While the
repository isn't small, it's not huge (it's
http://repo.or.cz/w/egit.git). I've tried the following:

$ git diff v0.4.0  > ~/t.diff
$ git diff v0.4.0 HEAD  > ~/t.diff
Both sit indefinitely eating most of 1 CPU
$ git fsck
Exits quickly with no output.

I don't mind going to a newer version of Git, but I'd like to have
some idea of the source of the problem before I start trying things.

Thanks!
John