JMX enabled Java application appears to open a random high order port when JMX client connects

I have successfully configured a helloworld JMX enabled program, and I can connect to it using jconsole JMX client from a remote location.

When I attempt to turn on iptables I noticed that a random high order port is established when a client logs in. Eventually I would like to monitor Java applications in firewall segregated network segments. Can we control the range the random port opens in?

I'll move this question to serverfault.com if suggested.