Debugger messes up rdoc

Sometimes it seems that ruby still has a way to go in terms of maturity. Today I got a strange error message when trying to build the rdoc files:

uninitialized constant RubyToken::AlreadyDefinedToken (NameError)

Any idea what it means? It turns out that I forgot to remove a require 'ruby-debug' somewhere in the code, which in turn includes some files from irb, which in turn is incompatible with rdoc. Duh…