You could try this product. But be sure to mix it with water and shake well. It is an oil and is very potent. I would apply it with a brush on the areas that he chews.
http://www.amazon.com/Saddler-JM-Co...P1KO/ref=sr_1_2?ie=UTF8&qid=1328922178&sr=8-2 I sprayed my front yard with this when my rude neighbor was brining her dog over in the morning to do his business. The dog refused to come into the yard. Plus I have a friend who lives on a farm and sprayed her front porch to keep the stray tom cats from spraying there.
http://www.amazon.com/Saddler-JM-Co...P1KO/ref=sr_1_2?ie=UTF8&qid=1328922178&sr=8-2 I sprayed my front yard with this when my rude neighbor was brining her dog over in the morning to do his business. The dog refused to come into the yard. Plus I have a friend who lives on a farm and sprayed her front porch to keep the stray tom cats from spraying there.