merging two repositories

[joel reed <joelwreed@gmail.com>]

I've been maintaining a project in git for a while and making use of 
http://repo.or.cz/w/tfs.git as a public repository. Since I also needed 
a project site, I set something up at Google Code, which of course, 
forces you to use subversion.

I added the files to subversion, checked them in, then a few weeks later 
decided I should learn how to use git-svn. So now I have two trees, one 
pure git using repo.or.cz, and the other made by git-svn against Google' 
subversion.

Is there anyway to merge these two repositories into one? I don't want 
to lose the http://repo.or.cz/w/tfs.git history, but I don't care about 
the Google subversion history.

I tried moving the .git/svn folder from the git-svn managed repository 
into the repo.or.cz .git folder, but as I expected, that didn't work. 
Life's never that easy! Anyway, if anyone knows how to merge these two 
repos, I would love to hear about it.

jr

PS. Maybe, a more generalized use case here is
  a) maintain a git tree for a while
  b) decide you have to stick code in subversion for others sometime 
later, but you still want to use git and keep your git history