i have the following code for search from database show return result to the page and show them with jqgrid, my code works fine with firefox but its not work on ie, when i use of utf8 like arabic letters, i set both of encoding of ie, and firefox to unicode(utf8)

onun html kodu

first name: <input type="text" id="firstname" onkeydown="doSearch(arguments[0]||event)" value="" class="mytextbox" /> 

<button onclick="gridReload()" id="submitButton" style="margin-right:100px;" class="Buttons">search</button> 

benim javascript kodu

function gridReload(){ 
    var name = jQuery("#firstname").val();

jQuery("#list2").jqGrid('setGridParam',{url:"<?php bloginfo('template_url'); ?>/post2.php?firstname="+firstname",page:1}).trigger("reloadGrid");

}

ve benim php kod

if(isset($_GET["firstname"]))
 $firstname = $_GET['firstname'];

mysql_query ( "set names utf8" );

if($firstname!='')
 $where= "  firstname LIKE '$firstname%'"; 

$SQL = "SELECT id,firstname,lastname FROM  mytable ".$where." 
     ORDER BY $sidx $sord LIMIT $start , $limit";

 $result = mysql_query( $SQL ) or die(mysql_error());
$responce->page = $page;
     $responce->total = $total_pages;
     $responce->records = $count;
 $i=0;
 while($row = mysql_fetch_array($result,MYSQL_ASSOC)) { 
     $responce->rows[$i]['id']=$row[id];
     $responce->rows[$i]['cell']=array(
     $row[id],$row[firstname],$row[lastname]);
     $i++; 
     }

 echo json_encode($responce); 

neden onun yani (i teste IE8 ile) çalışmak ama opera ve firefox ile çalışır

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