I have a Focus 1.8 Zetec Feb 01. I have recently noticed that both rear doors near the lower seal have started to rust. The pics show the underside of the door viewed from behind. The paintwork is bubbling. It looks to be more prevalent on the nearside door. Both of the front doors are fine with no evidence of rust forming. Can I get Ford to fix this under the Anti Perforation warranty? The car has been regularly serviced with stamps in the service book to show this.