QUOTE(Special_K @ May 12 2004, 07:14 PM)
What is it about that location?
The factory, in it's infinite wisdom, filled the area with foam and covered that with a sealer.
After a few years the sealer delaminates from a small area (at first) of the bodywork and lets moisture into the foam. The foam holds onto the moisture and creates a perfect environment for iron oxide formation.
Most of the typical rust prone areas on our cars are where moisture resides after the undercoating or body schutz fails.