This stuff works really well.
www.oceanearthstore.com/surf-accessories/ultimate-wetsuit-repair-kit/Glue the seam with the seal cement. Patch over it with the iron on patch. Good as new.
Follow the instructions fairly closely. It's easy to do.
With the iron on patch you need to have the iron at the right temperature. It is easy to start cooler and keep raising the temperature until the patch welds into place. It's really obvious when it's done right.
The seal cement has two advantages compared to other glues.
1. It paints on fairly neatly using the supplied brush. The others stick to everything in sight and make a mess. (You can rub the excess off the brush when it dries and use it again.)
2. You can close the tube and use it again and again until it is finished. It doesn't go off in the tube (well mine hasn't yet).
You can buy the kit at most surf shops, or you can order the components from McNett who make it.