[Exim] Anyone used Messagewall? (OT)

Sorry that this isn't really about exim, but given the amount of mail-admin
knowledge here it's the best place I know of to ask :)

Has anyone used/heard of/got opinions on Messagewall
(http://www.messagewall.org/)? It seems interesting to me but when i
searched I wasn't able to find anyone talking about it anywhere.

It looks to me as though a lot of its features could be done with
exim--some simply, some requiring a bit of configuration--but that it
might still be useful.

Thoughts?

DG