function extract_params($body) {
		$kvs = explode ( '&', $body );
		$decoded = array ();
		foreach ( $kvs as $kv ) {
			$kv = explode ( '=', $kv, 2 );
			$kv [0] = $this->safe_decode ( $kv [0] );
			$kv [1] = $this->safe_decode ( $kv [1] );
			$decoded [$kv [0]] = $kv [1];
		}
		return $decoded;
	}