code: public String toFtpCmdArgument() {
  	StringBuffer msg = new StringBuffer();
  	for (int i=0;i<datainfo.length;i++) {
  	    msg.append( String.valueOf(datainfo[i]) );
  	    if (i+1 != datainfo.length) msg.append( "," );
  	}
  	return msg.toString();
      }
docs: Returns the host-port information in the
  format used by PORT command.
  (h1,h2,h3,h4,p1,p2)
  
  @return host-port information in PORT command
  representation.