Hi Roadrunner,
I think this is a know issue with running Hyperic HQ Agents in Solaris Zones. The problem is the global loopback device. Obviously Zones provide only one loopback device. So the first starting Agents binds to the loopback device and the second, third one etc. can't bind because it's already in use.
I don't have a Zones test environment, but one idea is to use different ports for each Agent you start, e.g.
Global Zone Port 2144, Zone #1 Port 22144, Zone #2 Port 22145 etc.
HTH,
Mirko