Sail tape
Like you, I sail a 20-footer. I had a 1"x1" hole in my genoa. Bought some self-adhesive sail tape from West Marine, taped over both sides - and got an entire season out of the sail with no problems whatsoever. Mind you, I only use the genoa in relatively moderate winds: I don't know if the fix would have been so succesful on my working jib in a real blow.Still, tape's the way I'd go in your situation.Right now, the sail's at Sailcare, to get a quote for a more permanent fix. But, if they want to charge a lot - more West Marine tape for me.