po-devs/pokemon-online — pull request #212 by CrystalMoogle (2013-02-02 19:04:29+00:00)
Title: Fixing po:ignore and po:watchplayer and adding po:info to allow clicking of a link to a player's info

http://pokemon-online.eu/forums/showthread.php?18291-Chat-Option&p=249009#post249009
This gave me the idea. Basically you can just use scripts to make the names clickable links to challenges instead :3 (You can use styling etc to remove the underline and change colour to the player's name).
I'd take a screenshot of it in action, but it's sort of hard to see...