Cruise Control Disengages

The cruise control disengages on my 2001 3.4L Impala if I hit a bump in the road. Typically this occurs when I cross an overpass where there is a slight transition in the road surface and, of course, if I hit a pot hole. Its a pain in the neck because I have to tap the brakes to reset the cruise control then anticipate the next bump that will disengage it again. Any ideas how to fix it? Thanks.