git から svn を透過的に使う

Tracking and contributing to the trunk of a Subversion-managed project:

# Clone a repo (like git clone):
git-svn clone http://svn.foo.org/project/trunk
# Enter the newly cloned directory:
cd trunk
# You should be on master branch, double-check with git-branch
git branch
# Do some work and commit locally to git:
git commit ...
# Something is committed to SVN, rebase your local changes against the
# latest changes in SVN:
git-svn rebase
# Now commit your changes (that were committed previously using git) to SVN,
# as well as automatically updating your working HEAD:
git-svn dcommit
# Append svn:ignore settings to the default git exclude file:
git-svn show-ignore >> .git/info/exclude

http://www.kernel.org/pub/software/scm/git/docs/git-svn.html