Configuring fill-paragraph not to mash the subversion delimiter?

[Adam Funk]

Is there any easy way to set something in my ~/.emacs file so that
when I'm editing subversion commit messages and I use M-q to tidy up a
few lines of text, the fill-paragraph command will treat the standard
line 

--This line, and those below, will be ignored--

as not being part of the paragraph, even if there is no blank line
before it?