问Ajax成功和错误函数失败

EN

$(document).ready(function(){  
        $("form#updatejob").submit(function() {  
            function textreplace(x) {return text.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, "\\$&");}
            // we want to store the values from the form input box, then send via ajax below
            var job     = $("#job").attr("value");
            var description     = $("#description").val();
            description.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, "\\$&");
            var startDate   = $("#startDate").attr("value");
            var releaseDate = $("#releaseDate").attr("value");  
            var status  = $("#status").attr("value"); 
            $.ajax({
                beforeSend:textreplace(description),
                type: "POST",  
                url: "updatedjob.php",
                data: "jobID="+ job +"& description="+ description +"& startDate="+ startDate +"& releaseDate="+ releaseDate +"& status="+ status, 
                success: function(){  
                    $("form#updatejob").hide(function(){$("div.success").fadeIn();});  
                },
                error: function(XMLHttpRequest, textStatus, errorThrown) { 
                    alert("Status: " + textStatus); alert("Error: " + errorThrown); 
                }       
            });
            return false;  
        });  
});

<?php 
    include("connect.php"); 
    $job = trim($_POST['job']); 
    $startDate = trim($_POST['startDate']); 
    $releaseDate = trim($_POST['releaseDate']); 
    $mysqlstartdate = date('Y-m-d', strtotime($startDate)); 
    $mysqlreleasedate = date('Y-m-d', strtotime($releaseDate)); 
    $description = trim($_POST['description']); 
    $status = trim($_POST['status']); 
    $update = "UPDATE jobs SET startDate = '$mysqlstartdate', releaseDate = '$mysqlreleasedate', description = '$description', status = '$status' WHERE jobID = '$job' "; 
    $rsUpdate = mysql_query($update);
// or die(mysql_error()); mysql_close(); 
?>