I don't want to sound contrary, but why reinvent the wheel? basically, having a forwarding address @perlmonks.org would let you do what you're suggesting only when someone wanted to leave one of these 'longer /msg's' (which is exactly how i've been thinking about this too), they would just shoot an email to Petruchio@perlmonks.org
That way vroom does next to no work (add a script that puts an alias in a sendmail config upon a user achieving XYZ status), there's no need for monks to check any extra pages for messages they weren't already and there's no upgrade/enhancement worries on the code side should the monastery have a major overhaul or something (not to say it needs even the slightest tweak, but sometimes you just have to re-write code because it's there : )
"sometimes when you make a request for the head you don't
want the big, fat body...don't you go snickering."
-- Nathan Torkington UoP2K a.k.a gnat