From the Heinz website (www.heinz.com) on 5/05/2008:
Heinz Ketchup and Heinz Organic Ketchup do not contain any gluten (the distilled vinegar used is from corn sources). Also, Wine Vinegar, Distilled White Vinegar and Apple Cider Vinegar are gluten-free. Heinz Hot & Spicy Ketchup Kick'rs is gluten-free as well.
As for our other Heinz products, we are not able to guarantee that all ingredients would be gluten-free, since the source of an ingredient may change from time to time. We understand how difficult it can be finding foods that meet the requirements of a restricted diet, and we continue to look for ways to meet the dietary needs of our consumers.