Remove 'credential-osxkeychain'
I ended up deleting osxkeychain from the config file.
git config --global --edit
It seems MacPorts packages the keychain helper and that might be why it wasn't coming up as a recognized command for you.
You can install the helper directly by following these instructions:
via: Magnus Johansson @ http://insomniacgeek.com/how-to-add-your-git-password-in-the-mac-osx-keychain/
In order to not having enter your git based password every time you perform a git operation, here’s how you can store the git password in the Mac OSX keychain:
Check if you have the credential-osxkeychain helper already installed:
git credential-osxkeychain
If not, the download and install it:
curl http://github-media-downloads.s3.amazonaws.com/osx/git-credential-osxkeychain -o git-credential-osxkeychain sudo mv git-credential-osxkeychain /usr/local/bin sudo chmod u+x /usr/local/bin/git-credential-osxkeychain
And make git use the helper:
git config --global credential.helper osxkeychain