Tank Assembly problems of the 2006 Honda Odyssey

I have had my Honda Odyssey inspected several times and have complained about a clunking noise coming from underneath vehicle when it comes to a stop. I recently was told by a Honda representative (mechanic of Honda) that some of the Odyssey (2006 model) the noise is from the gas tank bumping. I was told this is just a characteristic of the Odyssey. I told them that sometimes the noise is really a loud and a hard clunk. I then was told just check and see how full the gas tank is at the time. I have researched and learned others have complained about the same problem. I don't how thiscould not be a safety issue when gas is involved? I think they should be doing something to correct this problem.