Aqauseal will ruin your suit! It has very low flexibility relative to neoprene and will cause tears, localize strain and reduce the flexibility of the suit a lot if you put it on large areas. It is OK for patching small punctures, addressing abrasion of a boot by your big to or your fin heel strap or a dab here or there on some gloves or on your knee, but you don't want to cover a seam with it or make large repairs or patches. Normal wetsuit glue is generally better for any repairs.
If a considerable portion of the seam of a wetsuit is degrading and leaking.. then the suit is not going to be warm and is probably reaching the end of it's useful life. Might work great for the summer if you dive in warm water.. lets the piss out.
I probably wouldn't try messing with it too much.
