I have not found that reducing the aperture makes any appreciable {reduction to chromatic aberration. See }.PanoTools. For information about chromatic aberration and how to fix see Correcting Distortion and Color Fringing by J. Brian Caldwell.
{Picture below `Blue Jay' by Adrian Ashfield. Taken with FZ10}
See Section for a lot Panorama Tools links.
Alternatively, chromatic aberration can be manually removed with drawing software. After transferring the photograph to a computer you can manipulate the photograph with GIMP (a free Photoshop-like program). Look at Mike Larson's instructions. In summary, Mike Larson reduces the saturation of the offending colours, in his case a purple/blue/cyan fringe. He also made some changes to the hue of one colour. Another option is to reduce the saturation of any areas which show chromatic aberration (using masks).