I think what you say is true. We have the same application(running in-core i.e., non-DMZ) connecting to the MQ server and it works fine. In fact it has not been cycled at all. Unfortuna ...
I have written a web application using MQ classes for Java(TM) Version 5.3. The application maintains the connection for a minute and tears it down if there is no activity. Once in a while ...