jQuery Grid Plugin - jqGrid

i am using the jqgrid example and added the onSelectRow to run some javascript code but I get undefined id and it can't find the row id even though I set the key and even set the row id in the server php code.

Here's the code:

jQuery(”#bigset”).jqGrid({

url:'bigset.php',

datatype: “json”,

height: 150,

colNames:['Index','Name', 'Code'],

colModel:[

{name:'id',index:'item_id', key:true, width:65},

{name:'item_name',index:'item_name', width:150},

{name:'item_cd',index:'item_cd', width:100}

],

rowNum:5,

//rowList:[10,20,30],

imgpath: 'themes/basic/images',

mtype: “GET”,

pager: jQuery('#pagerb'),

sortname: 'item_id',

viewrecords: true,

sortorder: “asc”,

onSelectRow: function() {alert(id);}

});

This is the section in php that sets the row id

while($row = mysql_fetch_array($result,MYSQL_ASSOC)) {

$responce->rows[$i]['id']=$row[item_id];

$responce->rows[$i]['cell']=array($row[item_id], $row[item_name],$row[item_cd]);

$i++;

}

Your help will be highly appreciated.

Son