asterisk users - Feb 2008 - Emagen (a Telrad VM solution) -- any way to replace with *?

Hi, all.  I've got a PoS Emagen VM system tied in with our Telrad PBX.  I
hate 'em both, but I'm stuck with the Telrad for the time being.  That
being said, does anyone know of a way to replace the VM solution with
Asterisk?  I'd -love- to get an Asterisk box in the loop, here.

Thanks,

-Ken