private function findNextMessage()
    {
        do
        {
            $data = fgets( $this->fh );
        } while ( !feof( $this->fh ) && substr( $data, 0, 5 ) !== "From " );

        if ( feof( $this->fh ) )
        {
            return false;
        }
        return ftell( $this->fh );
    }