The Jquery script that controls my tabcontainer gives an "object expected" runtime error. I honestly can't find the reason why:

$(document).ready(function() {



//When page loads...
 $(".tab_content").hide(); //Hide all content
 $("ul.tabs li:first").addClass("active").show(); //Activate first tab
 $(".tab_content:first").show(); //Show first tab content

 //On Click Event
 $("ul.tabs li").click(function() {

  $("ul.tabs li").removeClass("active"); //Remove any "active" class
  $(this).addClass("active"); //Add "active" class to selected tab
  $(".tab_content").hide(); //Hide all tab content

  var activeTab = $(this).find("a").attr("href"); //Find the href attribute value to identify the active tab + content
  $(activeTab).fadeIn(); //Fade in the active ID content
  return false;
 });

});

Has it something to do with the stylesheet?