[xhtml1.1] validazione form

[blur]

perchè non mi valida questo codice? :master:

<div id="box">		
<p style="text-decoration:underline" class="middle">Iscriviti alla Newsletter</p>
Inserisci qui la tua email:                                           
<form method="post" action="">
<input type="text" name="email" value="" size="13" />
<input type="submit" name="invia" value="invia" />
</form>
</div>

mi dice che: document type does not allow element "input" here; missing one of "ins", "del", "h1", "h2", "h3", "h4", "h5", "h6", "p", "div", "address", "fieldset" start-tag



grazie

[andr3a]

<form method="post" action="">
<div id="box">
<p style="text-decoration:underline" class="middle">Iscriviti alla Newsletter</p>
Inserisci qui la tua email:
<input type="text" name="email" value="" size="13" />
<input type="submit" name="invia" value="invia" />
</div>
</form>