If a URL ends in a ")", for example http://en.wikipedia.org/wiki/Talisman_(board_game) the URL will not be parsed correctly. The final ")" is omitted and thus the link does not work. That character is a valid character and URLs of that form are used a lot by Wikipedia.

See http://www.phpbb.com/community/viewtopic.php?f=46&t=1673795&start=0