Hi,
I only test the latest mojoPortal using the latest Mono OpenSuse VMWare image, which currently has Mono 2.6.3 and it works ok but has some issues. You may possibly have better luck using an older version of mojoPortal on the version of Mono you have, but it can be hit or miss.
Most discussions about mojoPortal on Mono are in our Linux/Mono forum.
Best,
Joe