Hey Bobo5727. I know you can see the rust and it IS THERE. However this is not a common problem on the mini van. Not to say that you might have gotten a van with a panel that was not prepared and coated and painted correctly. These thing can happen. However it is NOT a common problem.
You can talk to the dealer (if you bought it new) and see what they may do but I don't think you will find any help there. I am sorry to say.
I agree with Larry when he says that your door drains may have been clogged up. I see that alot with aftermarket rust preventive add-ons and people who park under trees alot. The junk/leaves get down inside the doors and windshield areas, block drain areas and collect water. Then the water is held to the vehicle surface and causes the rust reactions.
I know this does not help YOU , however I am with the rest on keeping my vehicles clean. I even clean inside the door sills and all other surfaces everytime I wash my car and I wax the whole area at least once a year.
Good luck to you.
Avatar: EconoVoyager Concept
2001 Dodge Grand Caravan Sport 3.3L
2004 Chrysler Pacifica AWD 3.5L