Holy Demons

Opa galera a quanto tempo nao particio hj estou voltando e com algumas duvidas, tenho esse codigo meu que fiz a muito tempo atras quando php 4 era o topo inclusive no 4 ele funciona e no 5 ta dando esse erro

<?php
$area=$_GET['area'] ; 
if(isset($area)) {
if($area=="adicionar") {
 ?><form action="?area=save_new" enctype="multipart/form-data" method="post" name="post_new" id="post_new">

 <table width="231" border="0" cellpadding="0" cellspacing="0">
	 <tr>
	 <td width="49">E-mail:</td>
	 <td width="182"><label>
	 <input name="email" type="text" class=campos_formulario id="email" size="30" />
 </label></td>
 </tr>
	 <tr>
	 <td>&nbsp;</td>
	 <td><label>
	 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
	 <input type="submit" name="ok" id="ok" class="botao_enviar" value="::: Cadastrar :::" />
	 </label></td>
 </tr>
 </table>
 </form>
 <?php 
}//fecha adicionar
	//-area save_new salva a new

		if($area=="save_new") {
			$email = $_POST['email'];
			}//fecha if porncipal	
//-Salva as informações
if($errors=="") {			
	mysql_query("INSERT INTO email (email,) VALUES ('$email')") or die ("Conexão invalida");
	}//fecha else
	}//fecha salvar
?>

Seguinte erro

Notice: Undefined index: area in D:\web\sites\php\sidy_thiago\index.php on line 283

linha 283
$area=$_GET['area'] ;