Mono rubygems and ironruby

Hello,
After unzipping ironruby-1.1.1 into /opt/ironruby-1.1.1 I tried to run
rubygems with mono ir.exe, but I failed. I tried to adjust some path
variables, but it still didn’t work, rubygems kept complaining about a
missing gem_prelude.rb. Does someone know how to make ironruby make eat
all
the stuff in /opt/ironruby-1.1.1/lib on linux?