--- includes/functions_user.php.ORIG	2008-12-12 16:20:38.000000000 +0100
+++ includes/functions_user.php	2009-03-30 16:08:59.252359303 +0200
@@ -165,6 +165,22 @@
 		return false;
 	}
 
+	$user_id=FALSE;
+	// External Check if available are only additional (if sucessful returns user_id, else return an ERROR-String)
+	$method = basename(trim($config['auth_method']));
+	include_once($phpbb_root_path . 'includes/auth/auth_' . $method . '.' . $phpEx);
+
+	$method = 'user_add_' . $method;
+	if (function_exists($method))
+	{
+		$external_msg = $method($user_row, $cp_data);
+		if (empty($external_msg) || !is_numeric($external_msg)) {
+			return false;
+		}
+		$user_id = $external_msg;
+		// proceed, to actualize the internal phpbb-structures (like group-mapping)
+	}
+
 	$sql_ary = array(
 		'username'			=> $user_row['username'],
 		'username_clean'	=> $username_clean,
@@ -244,10 +260,14 @@
 		}
 	}
 
+	if ($user_id && empty($sql_ary['user_id'])) $sql_ary['user_id'] = $user_id;
+
 	$sql = 'INSERT INTO ' . USERS_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary);
 	$db->sql_query($sql);
 
-	$user_id = $db->sql_nextid();
+	$nextid = $db->sql_nextid(); // false if no auto-increment occured
+	if ($nextid) $user_id = $nextid;
+	if (!$user_id) return false;
 
 	// Insert Custom Profile Fields
 	if ($cp_data !== false && sizeof($cp_data))
@@ -1345,11 +1365,25 @@
 */
 function validate_username($username, $allowed_username = false)
 {
-	global $config, $db, $user, $cache;
+	global $config, $db, $user, $cache, $phpEx, $phpbb_root_path;
 
 	$clean_username = utf8_clean_string($username);
 	$allowed_username = ($allowed_username === false) ? $user->data['username_clean'] : utf8_clean_string($allowed_username);
 
+	// External Check if available are only additional (only errors count)
+	$method = basename(trim($config['auth_method']));
+	include_once($phpbb_root_path . 'includes/auth/auth_' . $method . '.' . $phpEx);
+
+	$method = 'validate_username_' . $method;
+	if (function_exists($method))
+	{
+		$error = $method($username, $allowed_username);
+		if ($error)
+		{
+			return $error;
+		}
+	}
+
 	if ($allowed_username == $clean_username)
 	{
 		return false;
@@ -1586,7 +1620,7 @@
 */
 function validate_email($email, $allowed_email = false)
 {
-	global $config, $db, $user;
+	global $config, $db, $user, $phpEx, $phpbb_root_path;
 
 	$email = strtolower($email);
 	$allowed_email = ($allowed_email === false) ? strtolower($user->data['user_email']) : strtolower($allowed_email);
@@ -1596,6 +1630,21 @@
 		return false;
 	}
 
+	// External Check if available are only additional (only errors count)
+	$method = basename(trim($config['auth_method']));
+	include_once($phpbb_root_path . 'includes/auth/auth_' . $method . '.' . $phpEx);
+
+	$method = 'validate_email_' . $method;
+	if (function_exists($method))
+	{
+		$error = $method($email, $allowed_email);
+		if ($error)
+		{
+			return $error;
+		}
+	}
+
+
 	if (!preg_match('/^' . get_preg_expression('email') . '$/i', $email))
 	{
 		return 'EMAIL_INVALID';