// PHP.ini : allow_call_time_pass_reference = On
// somenone can override this ?
function neo_mailCheck($Email){
	// email well formatted ? can use SANITIZE stuff
	if(!preg_match('`^[[:alnum:]]([-_.]?[[:alnum:]])*@[[:alnum:]]([-_.]?[[:alnum:]])*\.([a-z]{2,4})$`', $Email)){
		exit('Email adress '.$Email.' not well formatted');
	}
	// Get domain
	list(,$domain ) = split('@',$Email);
	// Cherching data MX in DNS
	if (getmxrr($domain, $MXHost)){
		$ConnectAddress = $MXHost[0];
	} else {
		$ConnectAddress = $domain;
	}
	// Creating connexion on smtp port (25)
	$Connect = @fsockopen($ConnectAddress,25,&$errno,&$errstr);
	if($Connect){
		// test return 220
		if(preg_match('/^220/', $Out = fgets($Connect, 1024))){
			fputs ($Connect, "HELO {$_SERVER['HTTP_HOST']}
");
			$Out = fgets ( $Connect, 1024 );
			fputs ($Connect, "MAIL FROM: <{$Email}>
");
			$From = fgets ( $Connect, 1024 );
			fputs ($Connect, "RCPT TO: <{$Email}>
");
			$To = fgets ($Connect, 1024);
			fputs ($Connect, "QUIT
");
			fclose($Connect);
			// If command RCPT TO returns 250 ou 251 (cf: RFC)
			// Son email exist
			if (!preg_match ('/^250/', $To) && !preg_match ('/^251/', $To)){
				// Adress rejected by server
				return false;
			} else {
				// Adress accepted by server
				return true;
			}
		} else {
			// Server not answered
			return false;
		}
	} else {
		// Login on mail server impossible
		// You can see error with this :
		// echo $errno."-".$errstr;
		return false;
	}
}

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