private function getBoundary() {

		if(null === $this -> boundary) {
			$this -> boundary = md5(date('r', time()));
		}

		return $this -> boundary;
	}
private function getBoundary() {

		if(null === $this -> boundary) {
			$this -> boundary = md5(date('r', time()));
		}

		return $this -> boundary;
	}
private function getBoundary ( ) { if ( null === $ this -> boundary ) { $ this -> boundary = md5 ( date ( 'r' , time ( ) ) ) ; } return $ this -> boundary ; }
Generates if needed and returns the boundary
@return string
Generates if needed and returns the boundary