We have We Work Remotely: Remote jobs in design, programming, marketing and more for example. The ; is a valid character in URLs, so there's no reason why you should fear this in a live application.
Yes, and plus is a valid character in e-mail addresses, yet I switched to hyphens for my "plus-addressing" because so many Perl scripts couldn't deal with plusses. I'd regularly give out "jay+extension@my.domain" and get mail addressed to "jay@localhost; extension@my.domain".
So your first argument (we haven't seen any problems yet) is much more
convincing than your second (it's a valid character) 
Jay Levitt