Emacs git-mode feature request: support fill-paragraph correctly

Hi,

when I choose to commit in Emacs' git mode, I'm prompted to enter a commit message in a buffer that looks something like this:

   Author: Joe Doe <joe.doe@example.org>
   --- log message follows this line ---
   foo.txt: lots of important changes

Now, when I hit M-q (fill-paragraph), Emacs doesn't recognize that the "--- log message ..." line ought to be considered a paragraph separator. As a result, the re-filled buffer is messed up:

   Author: Joe Doe <joe.doe@example.org> --- log message follows
   this line --- foo.txt: lots of important changes

Other modes, such as message-mode, do support that kind of thing correctly, so apparently it is possible to configure what the editor considers as a paragraph. Is there some Emacs wizard out there who'd be kind enough to improve git-mode accordingly?

Take care, Peter