After some more hacking, dlding this tgz will give you full access to the 
link structure. Just look at the test case ;). 

Note that whatever I've written is under Ruby license, but the other stuff 
is under a GPL license. 

www.tua.ch/ruby/link/050128-link-4.1b-for-ruby.tgz

This is probably going to be a real release sometime soon. 

best regards, 
kaspar

hand manufactured code - www.tua.ch/ruby