I think the easiest thing is just to remove the / from the name of the product. Looks like this is running WP eCommerce - and that will be sucking in the name and using that for the rel attribute on that page.
EDIT: Also looks like this is a problem on many other products as well. I'd suggest replacing the / with a - instead.
EDIT AGAIN: This page, without a slash in the name, works:
http://cfferns.com/products-page/fer...tiquum-leslie/ so looks like that's the problem alright.