You state that you are new owners as of March 2009. Is the RV a 2008 or 2009 meaning this is still under warrany? If so, I would not waste any time and bring it for warranty repair.
If the RV is not under warranty, then I would advice as others have mentioned and see if you can find the leak. It could be the sink, pipes, roof leak running down the wall, water heater, broken line somewhere and dripping to a point that settles to a low point.
Good Luck with your repair!