Returned Type: 
XmlDocument
Returns an XML Document with the following structure:
<?xml version="1.0" encoding="utf-8" ?> 
<furesult> 
	<message><![CDATA[ OK ]]></message>
	<email>pippo@pippo.com</email> 
</furesult>
 
 
Where
    - <message> contains OK or Error description
- <email> if the command is OK this field contain the user's email address