I have been using git as an svn frontend for awhile. Recently the svn repository was moved. At first I thought I would just change the remote repository in .git/config to point to the new repository. I did that, but when I ran git svn rebase I would get an error saying
"Unable to determine upstream SVN information from git-svn history"
I noticed that I could fetch, but I couldn't rebase. I found an answer here after awhile Googling: http://git.or.cz/gitwiki/GitSvnSwitch
Now I am able to use my git repo again :)