John,

This bug ocuress becose IE don't have opacity as style attribute and

z.cur function in fx returns NaN.

Get the current size

z.cur = function(){

return parseFloat( jQuery.css(z.el,prop) );

};

z.cur with fix

Get the current size

z.cur = function(){

if (prop == "opacity" && window.ActiveXObject)

return parseFloat( jQuery.css(z.el,"filter").replace(/D+/, '') ||

100 ) / 100;

return parseFloat( jQuery.css(z.el,prop) );

};