Patching chiffon?

[virosus.livejournal.com]

So I bought a lively chiffon dress for a wedding I'll be attending, but when I got it home I managed to put a tear in the skirt. It's only about an inch long, and it's on an inside layer, so you can't see it, but I'm worried it will fray and spread. I put some liquid stitches goop around the edges, and it's doing well enough on the hanger, but I don't know that it'll hold up to actual wear. I'm looking for something that'll be a more permanent, durable patch. It doesn't need to look perfect, like I said, it's not on the outer layer of fabric, but it needs to be reasonably water proof. I was thinking maybe a fusible webbing? Any ideas?