Extra comma in animate causes error in IE7

Depending on your Superfish configuration, you may render a js with a single animation option, such as this:

jQuery(function(){
jQuery('#superfish-1').supersubs({minWidth: 12, maxWidth: 27, extraWidth: 1}).superfish({
delay: 1000,
animation: {opacity:'show',},
speed: 'normal',
autoArrows: false,
dropShadows: false});
});

The trailing comma in the animation line throws an error in IE7 (not IE8 +)

However, adding another option (in my case, adding a "slide in effect: vertical") adds a second element to the animation list. That element does not have a trailing comma, and IE7 stops throwing an error.