Error handlers are wrapped around user code called by the POA in response to incoming CORBA requests. By default, an error is handled and a CORBA exception is returned to the client.
If the variable corba:*orb-status-output* is set to a non-nil value, a backtrace is printed to the given stream designator.
If the variable corba:*poa-break-on-error-in-server* is set to a non-nil value, the debugger will be entered. When the user opts to continue, a CORBA exception will be returned to the client. Note that while debugging is going on, a synchronous call from a client will be hanging, waiting for a response.
Developing Component Software with CORBA - 7 Aug 2017