JQuery form submission and CakePHP controller


I am using Cakephp and Jquery for my application.

My JQuery code is


					var str,fields;
					    function showValues() {
					      str = $("form").serialize();
                  $(".submit").click(function (){
	     type: "POST",
	     url: "http://localhost/cake_1.2.1.8004/index.php/results/submit1",
	     data: "str="+str,

	     success: function(msg){
	      alert( "Data Saved: " + msg);

                    return false;
            });//submit click


while the alert inside click of submit function displays the entrie thing eg.. _method=POST&name=a

But when i post this value and retriving in the controller its displaying only _method=POST..

My controller code is like,

 function submit1($id = null)

   echo "in ctrller ".$_POST['str'];


How to get the entire value in the controller and to save..
Or is there any method to retrive ..
Please suggest me.....