Ports not displayed in firewall rules

I just installed NIS 2012 and have run into a problem when defining firewall rules.  If I define a new rule, the ports are displayed properly in the Communications section.  If I save that rule and do other things, then if I go back to the rule and click on Modify, go to the Communications section, the area where the ports should be displayed is obscured by the Add and Remove  buttons.  No ports are displayed.