Gimp is doing strange things..

[Marissa Verma]

hi.  ever since i installed the new version of windowmaker (along with a new videocard) on my computer the GIMP hasn't been working properly.  when i drag the mouse on an image to lets say, make a square it leaves a very annoying pattern in the mouses path.  its hard to descibe but it forms a negative of the background.  it makes it hard to see what im working on.  does anyone know what is causing this and what i could do to fix it. thank you, marissa