click function load on a page and not in another page.

click function load on a page and not in another page.

Hello all.

I'm quite a new jQuery user.
I've got a strange problem.
In an Ajax page I've made a jQuery script that works fine. It switch src between IMG tags:.
My script:
  1.                     $("#img_thumb1").click(function(){
  2.                         var src_img_thumb1 = $("#img_thumb1").attr('src');
  3.                         var src_img_main = $("#img_main").attr('src');
  4.                         $("#img_main").attr("src", src_img_thumb1);
  5.                         $("#img_thumb1").attr("src", src_img_main);
  6.                     });
The HTML:
  1. <a href="#">
  2.       <img id="img_main" src="flower.jpg">
  3. </a>
  4. <a href="#">
  5.       <img id="img_thumb1" src="tree.jpg">
  6. </a>
I've add the "a" tag for having the hand on the mouse pointer. There's certainly a more elegant way to do it.

So here is the problem, when I replicate the same code in a non Ajax page, it don't works.
jQuery works as this works:
  1.                     $(document).ready( function () {
  2.                         alert("Ok document ready")
  3.                     });
Someone have a solution, or can give me a way to debug the code?

Thanks.