Round corners on all images?

Ok,

I just learned how to make rounded corners on div areas, its pretty simple as long as one can grasp the basic prinicples of of left and right (I am challenged by this every day, if not more).

But what I really want to do now is template some method of images appearing in primary content areas to have automatically rounded corners. Has anyeone ever done this?

Based on the round div corners method of inserting images into the corners rotated the correct way, could I instead have a div area that would be the same size as the photo and then fill that div with the appropriate div areas and matching images, maybe transpartent gif's that would overlay on the four corners of the image? This would maybe meant inverting the corners so that the transparency was over the image area.

I'm really sleepy, does anyone understand me?