jQuery Grid Plugin - jqGrid

I'm trying to add a new row and get the product id in response.  Here is the section from my grid.

 .navButtonAdd("#products_pager",{caption:"Add Product",title:"Add New Product", buttonicon :'./images/add.png',
        onClickButton: function() {
                $("#products_list").editGridRow("new", {
                editData: { companyid: $("#currentCompany").val() },
                reloadAfterSubmit: true,
                closeAfterAdd: true,
                dataType: 'json',
                mtype: 'POST',
                afterSubmit: function(response) {
                        // this is where I can't seem to get any response
                }
                });
        }
   });
here is my json response from the server

{"page":1,"total":1,"records":1,"rows":[{"id":"104383","cell":["104383","123456","Product Name","Active","Hazard","Application","Profit Center","615","1"]}]}
this matches the colModel in the grid definition. 

I either get "[object xmlHttpRequest]" or undefined as the response