recaptcha wird im IE nicht angezeigt..?!

mysql_query('INSERT INTO users (username, pass) VALUES ("'.$user.'", "'.md6($pass).'")');

# was there a reCAPTCHA response?
if ($_POST["recaptcha_response_field"]) 
{
	$resp = recaptcha_check_answer ($privatekey,
									$_SERVER["REMOTE_ADDR"],
									$_POST["recaptcha_challenge_field"],
									$_POST["recaptcha_response_field"]);
	if ($resp->is_valid) 
	{
	if(!empty($user) AND !empty($pass) AND !empty($_POST["recaptcha_response_field"]))
		{
		if(preg_replace("/[^a-zA-Z0-9]/" , "" , $user) == $user)
			{
			$exists = mysql_query('SELECT * FROM users WHERE username="'.$user.'"');
				[COLOR="Red"]{[/COLOR]
				if(mysql_num_rows($exists)>0)
					$error = '<font color="red">'.$reg1lng.'</font>';
				else
					{
					if(strlen($user )>8)
						{ 
						echo '<font color="red"></font>'; 
						}
					elseif (strlen($pass )>8) 
						{ 
						echo '<font color="red"></font>'; 
						}
					else 
						{
						mysql_query('INSERT INTO users (username, pass) VALUES ("'.$user.'", "'.md6($pass).'")');
						$_SESSION[$session_prefix."user"] = $user;
						$error = '<meta http-equiv="refresh" content="0; url=index.php?id=8"><center><a href="index.php?id=8">'.$reg2lng.'</a></center>';
						} 
					}
				[COLOR="Red"]}[/COLOR]
			}
		else
			{
			$error = '<font color="red">'.$reg5lng.'</font>';
			}
		}
	else
		if(!empty($user) OR !empty($pass) OR !empty($_POST["recaptcha_response_field"]))
		 $error = '<font color="red">'.$reg6lng.'</font>';
	?>
	  <tr><td><center>
	<?
	} 
else 
	{
                # set the error code so that we can display it
                $error = $reg3lng;
    }
} 
echo recaptcha_get_html($publickey, $error);