Protocol registering

Hello everyone. I'm using suse 8.2 with ximian desktop 2, and I whenever I click a mail link I get an error saying "protocol not registered". But if I go to the application association menu, there's a command to associate "mail to" protocol with evolution, which is a mail program part of the ximian desktop. Besides this, I want to register also the "mms" internet protocol, and I have no idea how to do it. Any help? Thanks Juan Gallardo