Why do we capture the call stack when close() is called?

[Kevin Sutter]

Hi,
I've noticed that we capture the current call stack (via an
IllegalStateException creation) when close() is invoked on the
AbstractBrokerFactory and when free() is invoked on BrokerImpl.  Then, if or
when assertOpen "fails" we include this exception (and call stack) as the
cause of a new IllegalStateException.  I suppose this can be useful for a
user that accidentally attempts to use a closed broker.  But, capturing this
information in "production" mode is kind of expensive.  Do we need this
processing at all?  If so, could we at least gate it's usage on a TRACE or
DEBUG setting?  Or, any other ideas?

Thanks,
Kevin