Request met ajax

<?php

  $habbo=$_REQUEST['habbonaam'];
  $username=$_REQUEST['username'];
  $text=$_REQUEST['text'];

		if($text = "") {
	echo ubb('[fullalert]Je moet wel een tekst invoeren voordat je een bericht in het gastenboek kunt zetten!<br>
			   <input type="button" value="Sluiten" onclick="javascript:melding_close();" />[/fullalert]');
		}else{
	mysql_query('INSERT INTO guestbook (to_user,from_user,text,date,ip) VALUES ("'.$habbo.'","'.$username.'","'.$text.'",NOW(),"'.$_SERVER['REMOTE_ADDR'].'")"');

	echo'<table>
    <tr><td width="100%"><table width="100%" style="border: dashed 1px; border-color: #EFEFEF;" cellspacing="0" cellpadding="0">
      <tr>
        <td style="background: #EFEFEF;"><div style="float: left; margin-top: 5px;"><img src="http://www.habbo.nl/habbo-imaging/avatarimage?user='.$_SESSION['username'].'&amp;action=sta&amp;frame=3&amp;direction=2&amp;head_direction=2&amp;gesture=sml&amp;size=s&amp;img_format=png" border="0" onerror="this.src=(\'http://www.habbowereld.nl/assets/img/site/error_habboSmall.png\')" /></div>
          <div style="float: left; margin-left: -25px;"><strong><a href="http://www.habbowereld.nl/leden/profiel/'.$_SESSION['username'].'">'.$_SESSION['username'].'</a></strong></div><br>'.userbb($text);.'
          <div align="right" style="margin-bottom: 5px; margin-right: 5px;"><font style="color: gray; font-size: 10px;">'.date("d-m-Y")'.</font></div>
         </td>
      </tr>
    </table>
    </td></tr></table>';
		}
		
	?>

<?php
$book_sql = mysql_query("SELECT *,DATE_FORMAT(date, '%d-%m-%Y') AS date FROM guestbook WHERE to_user = '".$user['username']."' ORDER BY date");
			
		echo ubb('<a name="guestbook"></a>[box=Gastenboek]<div style="height: 132px; overflow-y: scroll; overflow-x: hidden;"><table width="100%" border="0" cellpadding="0" cellspacing="2">');
while($book_row = mysql_fetch_array($book_sql)) {

		$writer_sql = mysql_query("SELECT *,DATE_FORMAT(register, '%d-%m-%Y') AS register FROM users WHERE username='".$book_row['from_user']."'");
		$writer = mysql_fetch_array($writer_sql);
		?>
        <tr><td width="100%"><table width="100%" style="border: dashed 1px; border-color: #EFEFEF;" cellspacing="0" cellpadding="0">
      <tr>
        <td style="background: #EFEFEF;"><div style="float: left; margin-top: 5px;"><img src="http://www.habbo.nl/habbo-imaging/avatarimage?user=<? echo $writer['habbo']; ?>&amp;action=sta&amp;frame=3&amp;direction=2&amp;head_direction=2&amp;gesture=sml&amp;size=s&amp;img_format=png" border="0" onerror="this.src=('http://www.habbowereld.nl/assets/img/site/error_habboSmall.png')" /></div>
          <? if(htmlentities($_GET['id']) == $_SESSION['username'] || htmlentities($_GET['page']) == $_SESSION['username']) {
			echo'<a target="_blank" href="http://www.habbowereld.nl/leden/guestbook/'.$book_row['id'].'/delete"><img src="http://habbowereld.nl/v4/assets/img/icon/close.gif" align="right" border="0" /></a>';
		}  ?>
          <div style="float: left; margin-left: -25px;"><strong><a href="http://www.habbowereld.nl/leden/profiel/<? echo $writer['username']; ?>"><? echo $writer['username']; ?></a></strong></div><br><? echo userbb($book_row['text']); ?>
          <div align="right" style="margin-bottom: 5px; margin-right: 5px;"><font style="color: gray; font-size: 10px;"><?php
						echo $book_row['date']; ?></font></div>
         </td>
      </tr>
    </table>
    </td></tr>
		<?
		} ?>
		</table><div id="new_message"></div></div>
        		<form method="post" action="/leden/profiel/<?=$user['username'];?>">
        		<div id="masterdiv">
				 <div align="right" style="padding-top: 5px;" onclick="SwitchMenu('sub1')"><input type="button" name="AB-OC" value="Reactie toevoegen" /></div>
                 
                 <span class="AddBook" id="sub1" style="display: none;">
                 <input type="hidden" id="habbonaam" name="habbonaam"  value="<?=$_GET['id'];?>" />
                 <input type="hidden" id="username" name="username" value="<?=$_SESSION['username'];?>" />
                 <textarea id="text" name="text" rows="5" cols="43"></textarea><br>
                 <input  type='button' onclick="newBook(this.form);SwitchMenu('sub1');"; value="submit"/>
                 
                 
                 </span>
                 	</div>
<div id="status"></div>
                 </form>
				 
				 
				 <? echo ubb('[/box]');
		?>

<script type="text/javascript">
//AJAXPOST GB
function newBook(myform)
{

      var message="habbonaam="+myform.elements["habbonaam"].value+"&username="+myform.elements["username"].value+"&text="+myform.elements["text"].value;
	  var message
     var url="POST_gb.php";
var request=null;

    if(window.XMLHttpRequest)   
   {

   request=new XMLHttpRequest();
   }
   else if(window.ActiveXObject)
   {

   request = new ActiveXObject("Microsoft.XMLHTTP");
   }
   
   if(request)
   {
   request.open("POST",url);
   request.setRequestHeader("Content-Type",
"application/x-www-form-urlencoded; charset=UTF-8");

request.onreadystatechange = function() {
  if(request.readyState==0)
document.getElementById('status').innerHTML='Uninitialized';
else  if(request.readyState==1)
document.getElementById('status').innerHTML='Loading...';
else  if(request.readyState==2)
document.getElementById('status').innerHTML='Loaded';
else  if(request.readyState==3)
document.getElementById('status').innerHTML='Interactive';
else  if(request.readyState==4)
{
document.getElementById('status').innerHTML='Completed';

document.getElementById("new_message").innerHTML =
request.responseText;
}

}
request.send(message);
   


   
   }
   else
   document.getElementById('Txtdata').value='Nothing';
}
</script>