2001 Other Plymouth Models water getting into the trunk well

I recently bought a Plymouth Neon for my daughter to drive to high school. The first rain after I obtained the car I noticed that the wheel well in the trunk had several inches of water in it. The rear seats let down and with a flashlight in hand I got into the trunk and had water hosed over the back of the car for several minutes. There was no visible water dripping into the car and so I spent several hours cleaning and drying. I thought the problem was eliminated but the next time it rained once again the water was in the trunk well and also in the rear passanger foot well. I have been to a Dodge service departments seeking solutions but they seem as if it is a completely new problem to them and they suggested watching from the inside of the trunk with water be hosed over the back. When I told them that I had already tried that they sent me to an auto body repair shop. I t was suggested there to check for leakage around the rear tail lights. I took them out and used a heavy bead of clear silicone any where it appeared that water could leak past them. No success! Over the past few days I have asked several owners of Dodge and Plymouth Neons if they have a water problem like mine. Four out of seven say they fight the same problem. May I ask you for any information that you might have which might help solve this problem? Also do you know of any recall that has to do with this. Finally it really seems strange to me that the two Dodge Dealers service departments here in Springfield, Mo. Area are not aware that this is a problem with their product when so many owner are.