It looks like you are trying to add a parameter to the facebook url?
The fact that you are getthing the invalid url error means you are on the right track because you are messing with the url. Considering you are triny to add a query or paremeter to the url and it isn't working, I'm getting you aren't using '?' or '&'. '?' starts a query and '&' continues it:
www.website.com/?param1=value1¶m2=value2
If your adding onto the facebook url, chances are it already has a string of queries, you'd have to check, but if so you can just add onto it with &.
@Jsum - I believe he's getting the error because he's probably seeing this in the compiled code:
http://facebook.com/share?module.link.href
that's why I was wondering where that link field was coming from since it's not getting the dictionary contents. It's just getting module.link.href as plain text.