NoMethod Error IronRuby clean install

Question

Hi All,

Just following these instructions to install IronRuby and rake to get .Net builds

http://www.tobinharris.com/past/2009/8/17/automating-net-development-and-nhibernate-with-ironruby-rake/

All looks good, add the location of ir.exe to the windows path variables and it finds it fine. However when i do this

igem install rake

it returns this error? I can't find anything on this on google?? what am i doing wrong??

(ir):1: undefined method 'rake' for main:object (NoMethodError)

Any ideas?