I have a "website" custom field in a user submitted post type form. It's not validating the URLs below as a website. They definitely are though. The only thought I had was maybe the single tick character was being explicitly checked and fails in the first one?
http://www.thehookuptackle.com/fishing-Soft+Plastics/Hag's/Tornado
http://www.thehookuptackle.com/fishing-Rods/G-Loomis+Rep+Samples/NRX+Casting+Rods
thanks!