public function socialUnlink($provider, $userid = null)
	{
		$this->debug->groupCollapsed(__METHOD__);
		if ($userid === null) {
			$userid = $this->userid;
		}
		$where = array(
			'userid'	=> $userid,
			'provider'	=> strtolower($provider),
		);
		$this->db->rowMan('user_social', null, $where);
		$this->log('sociaUnlink', $userid, array(
			'provider' => strtolower($provider),
		));
		$this->debug->groupEnd();
		return;
	}