IE8: SCRIPT438: Object doesn't support property or method 'radmenu'

[moniuch]

The title says what I'm getting in the console of IE8 after the radmenu has already been constructed. This is obviously not true, as - when I type in the console: jQuery.fn.radmenu - I'm being returned the code of the plugin - which shows the radmenu IS a function.

Below I'm pasting the code I'm using.

(function($){
  $(function(){

    var elCount = $("#radial_container").find('.item').length;
    var radii = [100,120,120,120,150,190,200,200,200,200]; 
    var cy =    [100,110,110,130,140,190,220,220]; // tested elCount: 2, 3, 4, 5, 6, 7, 8

    $("#radial_container").radmenu({
      listClass: 'list',
      itemClass: 'item',
      radius: (radii[elCount-1]) ? radii[elCount-1] : 200,
      animSpeed: 300,
      centerX: 220,
      centerY: (cy[elCount-1]) ? cy[elCount-1] : 200,
      selectEvent: "click",
      angleOffset: -90
    })
    .radmenu("show").radmenu("shuffle").radmenu("shuffle").radmenu("shuffle");

    $('.zb-mini').live('mouseenter', function(){$(this).addClass('hover')});
    $('.zb-maxi').live('mouseleave mouseout', function(){$('.zb-mini').removeClass('hover')});

  });
})(jQuery);