ruby18-rbtree broken

[Dieter Baron <dillo%danbala.tuwien.ac.at@localhost>]

hi,

with current pkgsrc, ruby18-rbtree cannot be loaded:

$ ruby18 /usr/pkg/lib/ruby/gems/1.8/gems/rbtree-0.2.0/test.rb
/usr/pkg/lib/ruby/gems/1.8/gems/rbtree-0.2.0/test.rb:1:in `require':
no such file to load -- rbtree (LoadError)
        from /usr/pkg/lib/ruby/gems/1.8/gems/rbtree-0.2.0/test.rb:1

line 1 of test.rb:
require "rbtree"

The package contains these files with rbtree in the basename:
        lib/ruby/gems/1.8/cache/rbtree-0.2.0.gem
        lib/ruby/gems/1.8/gems/rbtree-0.2.0/rbtree.c
        lib/ruby/gems/1.8/gems/rbtree-0.2.0/rbtree.so
        lib/ruby/gems/1.8/specifications/rbtree-0.2.0.gemspec
        lib/ruby/gems/1.8/doc/rbtree-0.2.0/rdoc/files/rbtree_c.html
        lib/ruby/gems/1.8/doc/rbtree-0.2.0/ri/MultiRBTree/to_rbtree-i.yaml

  I don't speak ruby, so I don't know how to debug this.  Any help
would be appreciated.

                                        yours,
                                        dillo