This is not really appropriate for Emacs. Installing Emacs should not force users of other editors to receive a system-wide policy to use Emacs for editing these types of files (however sympathetic I am to evangelizing those poor heathens. :-)
The idea as such has some merit. Debian already provides a facility for generic redirection to the user's preferred editor, so this suggestion could be implemented with /usr/bin/editor instead of emacsclient (this also solves the issue of allowing users to prefer emacs over emacsclient). However, it is unobvious to me which package to reassign this bug to. mime-support contains the tool for updating /etc/mailcap so that's what I would suggest, but I leave it to more competent people to possibly find a better route to take this. /* era */ -- If this were a real .signature, it would suck less. Well, maybe not. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org