I recently upgraded to Mac OSX 10.8.1, and found that I needed to reinstall Git. I did that, and Git works fine in the command line now.
However, when I run RubyMine, it says "Can't start git, probably the path to the Git executable is not valid. Fix it." It was giving me error=2.
So I went through a number of steps (http://stackoverflow.com/questions/4725389/how-to-get-started-with-git-on-mac) and found that my git executable is in /usr/local/git/bin. This now gives me error=13, "permission denied".
Even after making sure that everything inside /usr/local/git/bin was chmod'd to 755 (I also tried 777 for good measure.), and that it was marked as executable, it still won't work.
I am not sure what else to try. My RubyMine is 4.5.3.