circular overlay projection problem

[Jackie]

I’m currently using the ‘GroundOverlay’ function within a KML file to display an circular image.  I know the circle is 48 degrees in diameter, and I want it to look like a circle when I overlay it on the earth.  Rather than being a perfect circle though, it’s distorted, most visibly at the poles.  I think the reason for the distortion is that GoogleEarth assumes my original image used a map projection, so GE “unprojects” my image, creating the distortion.  Is there a way to overlay my circular image as a circle through KML or the maps API by turning off the projection?  Or is my only option to project my circular image into a simple cylindrical projection before I call GroundOverlay on it?  I'd really prefer the first option if it exists.