Warbler and rvm - Could not find RubyGem warbler when running WARBLE

/var/lib/hudson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:900:in `report_activate_error': Could not find RubyGem warbler (>= 0) (Gem::LoadError)
    from /var/l开发者_如何学Goib/hudson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:248:in `activate'
    from /var/lib/hudson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:1276:in `gem'
    from /var/lib/hudson/.rvm/gems/ruby-1.9.2-p180/bin/warble:18:in `<main>'

This is the error I get. I definitely have warbler though - I only have the executable "warble" because I've rvm gem installed warbler.

Any help?

EDIT: It should be available:

GEM_HOME:     "/var/lib/hudson/.rvm/gems/ruby-1.9.2-p180"
GEM_PATH:     "/var/lib/hudson/.rvm/gems/ruby-1.9.2-p180:/var/lib/hudson/.rvm/gems/ruby-1.9.2-p180@global"

/var/lib/hudson/.rvm/gems/ruby-1.9.2-p180/gems does indeed contain warbler-1.3.0. I ran the same setup script on the same machine as a different user and it finds it fine.

EDIT2: Alright, I used some puts debugging in rubygems.rb and the part where it loads the GEM_PATH isn't working... even though my GEM_PATH is defined by rvm (and, to be pedantic, I've tried manually copying it, as well), when run GEM_PATH is coming up as blank. Any ideas about that?