git svn already set … wanted to set to:

I am trying to clone/fetch svn branch with git-svn:

git config --add svn-remote.stable-2012-03-29.url https://some_host/branch
git config --add svn-remote.stable-2012-03-29.fetch :refs/remotes/stable-2012-03-29
git svn fetch stable-2012-03-29

which gives me this error message:

svn-remote.stable-2012-03-29.url already set: https://some_host/branch/ wanted to set to: https://some_host/

I know that I probably can fix this by re-fetching all svn-repo from scratch, but it will take months or even years (due to size of repo).

So, is there any solutions?