jquery text resizer does not work :(

jquery text resizer does not work :(

Hey :)
I'm begginer in juery and I'm trying to add icons increasing and decreasing text.
I found the code in net, but it does not work properly, because after one click on icon increasing font, text decrease, but it works fine later.

Demo is here: http://www.queness.com/post/3956/quick-and-easy-jquery-font-resizer-tutorial
Tips under the article does not work

The code is:

<script type="text/javascript">
$(document).ready(function () {

   //min font size
   var min=9;    

   //max font size
   var max=16;   
   
   //grab the default font size
   var reset = $('p').css('fontSize');
   
   //font resize these elements
   var elm = $('p.intro, p.ending'); 
   
   //set the default font size and remove px from the value
   var size = str_replace(reset, 'px', '');
   
   //Increase font size
   $('a.fontSizePlus').click(function() {
      
      //if the font size is lower or equal than the max value
      if (size<=max) {
         
         //increase the size
         size++;
         
         //set the font size
         elm.css({'fontSize' : size});
      }
      
      //cancel a click event
      return false;   
      
   });

   $('a.fontSizeMinus').click(function() {

      //if the font size is greater or equal than min value
      if (size>=min) {
         
         //decrease the size
         size--;
         
         //set the font size
         elm.css({'fontSize' : size});
      }
      
      //cancel a click event
      return false;   
      
   });
   
   //Reset the font size
   $('a.fontReset').click(function () {
      
      //set the default font size   
       elm.css({'fontSize' : reset});      
   });
      
});

//A string replace function
function str_replace(haystack, needle, replacement) {
   var temp = haystack.split(needle);
   return temp.join(replacement);
}
</script>