I can't find the original post put someone posted about having a rust problem on the sills. I did some investigation and discovered a few things about this cars construction. The rocker panels are plastic but only attached to the body on top below there is a 2 or 3 inch gap and the covers are bolted onto the cars body with brackets. The body under there is welded to the frame I am assuming. I took a mirror with a handle on it to get a better look as with my handicap I can't lay down on the ground. There are some drain holes along this line of body work. I went into the house and got my jewelers screwdrivers. The smallest of these would not fit into the drain holes. So I got a single edge razor blade and that fit into the drain holes, not much room for water to drain out of. Also where the door hinges meet the body and at the top of the rocker panel there is a drain hole which drains to the ground. I am thinking that winters up here in New England could do a job in the area behind the rocker panels and that area should also be washed or at least hosed down. As this might be were the rust developed on the posters car. Also I noticed when I washed the car and open the front doors to wipe off the sills water pools on the sills, never saw anything like that on any car I owned. The sills usually have a slight tilt downward so water can run down onto the street. All I have to say is that Jaguar did some strange construction in these areas. I have no rust on my car but I am going to keep an eye on these areas as time goes on.