Qtruby problem, can't show rescourcefile

I created with the qtdesigner a MainWindowForm and saved it as *.ui then
I converted it with rbuic to a ruby recoursefile named win.rb and I’m
trying to use it with trunk.rb but I’m always getting this fanzy

y$ ruby trunk.rb
/usr/lib/ruby/1.8/Qt/qtruby.rb:1186:in ==': undefined methodto_i’ for
true:TrueClass (NoMethodError)
from /usr/lib/ruby/1.8/Qt/qtruby.rb:931:in initialize' from /usr/lib/ruby/1.8/Qt/qtruby.rb:1367:incall’
from /usr/lib/ruby/1.8/Qt/qtruby.rb:1367:in try_initialize' from /usr/lib/ruby/1.8/Qt/qtruby.rb:1366:incatch’
from /usr/lib/ruby/1.8/Qt/qtruby.rb:1366:in try_initialize' from ./win.rb:132:innew’
from ./win.rb:132:in initialize' from trunk.rb:7:ininitialize’
from trunk.rb:15:in `new’
from trunk.rb:15

something seems wrong with my trunk.rb but I can’t figure out what. Can
someone of you help?