I recently attended a class on mold. The experts say that the proper way to remove mold from drywall or paneling is to remove the panels and replace them with new ones. If you decide to clean up the mold instead of removing the panels, they suggested using dish washing detergent because dish washing detergent actually removes more of the mold "root" than bleach. The experts said that cleaning the mold is only a temporary solution and that it will eventually reappear. Finally, whatever you do, you've got to get rid of the moisture if you want to keep the mold away. This can be acomplished with de-humidifiers, sump pumps, an air conditioner, or whatever else it takes to get rid of the moisture.
The EPA has a website that lists the steps to remediate mold. (Try a Google search)
Good Luck