Have you ever had this happen to you?

http://www.thingiverse.com/thing:636350

It did for me. I designed this to prevent future door damage. By increasing the surface area of the door contact, the force on the door is significantly reduced.

Simply print and replace the original cap. This is meant for the fixed side and not the adjustable side. Since the door stop is not cast to precision, you might need to scale the the part to match your door stop. Depending on your printer, you may or may not need support.