OS X: using emacs as default mailer?

[John Owens]

I'd like to use emacs as my default mailer in OS X. When I click on a mailto:
link, I'd like gnuclient to call compose-mail. I have this working manually
from the command line no problem. What I believe I need to do is to run
OS X's Mail.app and then select the default mailer within the preferences.
However, a small shell script I wrote to call gnuclient does NOT appear
(or rather, it's greyed out, not valid) in the select-a-new-application
dialog that allows me to select a new app default. Surely this is a
problem others have run into ... any advice would be appreciated on
what sort of app would work.

(One suggestion: http://sourceforge.net/projects/mailtomutt , but that's
pretty mutt-specific.)

JDO