Jquery toggle code only works in IE , but not Chrome/FF

Jquery toggle code only works in IE , but not Chrome/FF

Hi guys, i have some jquery code that shows and hides some content. but it only works in IE but not FF or chrome. Can anyone please help me with that? 
  3. <div class="critical">
  4.       <div class="rec">
  5. <div class="header">
  6. <a><img alt="open this item" src="/images/rec.png" /></a>
  7.                 <h3>Know your break-even point </h3>
  8.        <a><span class="more">more... </span></a>
  9.         </div>
  10.       <div class="content" style="display: none;">
  11. <div class="reportIntro">
  12. <p>You need to understand how to work... </p>
  13.                   </div>
  14.             </div>
  15.       </div>
  16. </div>
  17. <div class="important">
  19.       <div class="rec">
  20. <div class="header">
  21. <a><img alt="open this item" src="/images/rec.png" /></a>
  22.                 <h3>Know your break-even point </h3>
  23. <a><span class="more">more... </span></a>
  24.         </div>
  25. <div class="content" style="display: none;">
  26. <div class="reportIntro">
  27. <p>You need to understand how to live... </p>
  28.                   </div>
  29.             </div>
  30.       </div>
  31. </div>

  34. <script type="text/javascript">
  35. jQuery(".header a").click(function() 
  36. {
  37. if (jQuery.browser.msie && jQuery.browser.version == '6.0') {
  38. if (jQuery(this).parent().find("img").attr("src") == "Dwn.gif") 
  39. {
  40. jQuery(this).parent().find("img").attr('src', 'Rgt.gif');
  41. jQuery(this).parent().find("span").text("more...");
  42. }
  43. else 
  44. {
  45. jQuery(this).parent().find("img").attr('src', 'Dwn.gif');
  46. jQuery(this).parent().find("span").text("less...");
  47. }
  48. }
  49. else {
  50. if (jQuery(this).parent().find("img").attr("src") == "Dwn.png") 
  51. {
  52. jQuery(this).parent().find("img").attr('src', 'Rgt.png');
  53. jQuery(this).find("span").text("more...");
  54. }
  55. else 
  56. {
  57. jQuery(this).parent().find("img").attr('src', 'Dwn.png');
  58. jQuery(this).find("span").text("less...");
  59. }
  60. }
  61. jQuery(this).parent().next().animate({ height: "toggle", opacity: "toggle" }, 500);
  62. });
  63. </script>
in IE, all the pics/text change fine. the content are toggled as well. but in FF/Chrome the text "more" has been changed to "less" but become unclickable.

Any help will be appreciated.