According to this USDA Plant Profile Map, Bignonia capreolata (Crossvine) grows natively to Mobile County, Alabama. This is usually the first thing we look at when we are trying to diagnose a problem with a plant. Trying to grow a plant in the wrong climate or soil is frequently the first problem we find. In this case, however, it is obviously in the right spot.
Here is a previous Mr. Smarty Plants answer on care of crossvine. From BackyardGardener.com, here is an article on Bignonia capreolata (Crossvine). Scroll down the page and you will find information about spider mites, mealy bugs and fungus, all of which can affect this plant. From your description, we would suspect fungus, possibly caused by poor circulation of air or not enough sun on the plant. Since we can't see the plant (and, sorry, we no longer can accept pictures) we will have to give you information to make your own diagnosis.