Yes. It's a known bug in ORB connection management. What's happening here is, the connectionCache that maintains both inbound and outbound connections does not reclaim connections, upon ORB destroy() call. There is a connection reclaim() logic in place, but does not kick in, until it reaches certain watermark levels. Since, a single client can have a multiple ORBs and thereby multiple outbound connections (in the reported case) , with each cache having exactly one connection which leaks up on ORB exit. This leak multiplies based on the number of ORBs and time period over which client stays live, up and running.
The solution is, to walk through the connection cache and close each connection,
no matter what the watermark levels are. This can be done at the corba transport manager close() call.