replaying commits against CVS

I am not looking for a full-blown 2 way gateway. But we do work quite
a bit on some projects where the upstream is using CVS, and it'd be
great to be able to replay our history against CVS. (And thus, when
the commits are echoed back, git-cherry will do the right thing and
skip them).

My current plan is to take git-apply-mbox and transform it to perform
the nasty deed. But smarter people have been merging mbox-formatted
patches automatically for ages, and perhaps there's a script out there
that is known to work reliably.

cheers,


martin