So I figured out how to get mono to update on a gentoo hardened kernel today...

Requires: pax softmode to be enable in kernel

#> sysctl pax.softmode=1
#> emerge mono
#> sysctl pax.softmode=1 && paxctl -m `which mono`

*ding* fries are done!

Also made an ebuild for mono-1.9.1 and libgdiplus-1.9 ... so now my mono build is completely up-to-date.