Chat clients that detect links and convert them to clickable form are thrown when something that looks like the beginning of a uri (example.com) appears in a fopnu link anywhere after a bracket.

This seems to be because… "A host identified by an Internet Protocol literal address, version 6  or later, is distinguished by enclosing the IP literal within square brackets ("[" and "]").  This is the only place where square bracket characters are allowed in the URI syntax." - http://www.ietf.org/rfc/rfc3986.txt