<!--
function highlight(img) {
    var start_index;
    var end_index;
    var filename;
    var extension;
    
    start_index = img.src.lastIndexOf("/");
    end_index = img.src.lastIndexOf(".") ;

    filename = img.src.substring(start_index, end_index);
    extension = img.src.substring(end_index + 1);

    filename += "_over";

    img.src = 
	img.src.substring(0, start_index)
	+ filename
	+ "." + extension;
 }
function unhighlight(img) {
    var end_pathname_index;
    var start_extension_index;
    var path_filename;
    var extension;
    
    end_pathname_index = img.src.lastIndexOf("_");
    start_extension_index = img.src.lastIndexOf(".") ;

    path_filename = img.src.substring(0, end_pathname_index);
    extension = img.src.substring(start_extension_index + 1);

    img.src = 
	path_filename
	+ "." + extension;
}
//-->