Carrier/rack problems of the 2004 Jeep Cherokee

Plastic surrounding door handles cracked. First incident was on right rear door. I assumed my child was playing roughly. Soon after a similar crack appeared in the front door on the drivers side. Next came the front passenger door and now all four door panels have cracks in the plastic surrounding the door handles. The left rear door can not be opened from the inside and the right rear door does not open consistently. I expect it to fail completely soon. While reviewing Jeep message boards I found a lot of people with 2005-2010 Jeeps have experienced similar failures. My dealer, bob baker Jeep in carlsbad CA, says the doors are not covered and suggested replacing the entire panel on each door.