Self-invoking Modules Error Out In IE6/7?

I have a grouping of private/public functions defined under a namespace like so:


var Effects = function() {
// private variables
var shades = new Array("#ff9", "#ffa", "#ffb", "#ffc", "#ffd", "#ffe", "#fff");
var blindInterval = 20;
var skipFactor = 19;
var highlightInterval = 200;

// private methods
var fade = function( id, idx ) {
//
};
var resize = function( id, queue ) {
//
}
};
var getHiddenHeight = function( id ) {
//
}
};

// public methods
return {
highlight : function( id, interval ) {
//
},
blind : function( el, skip, interval ) {
//
},
toggle : function( id ) {
//
},
zebra : function( id ) {
//
},
};
}();


From mozilla, I'm able to do what's expected by calling the functions like: 'table-1' )" but in IE6 and IE7 I get a "Effects is not defined" error. That's puzzling to me, since they're both defined through a var Effects = function(), and the function itself is self-invoking.