This message means that your application is trying to use more connections than are in the resource adapter's connection pool. The pool (which you will have configured yourself) is managed jointly by the resource adapter and the application server runtime. It's nothing to do with the broker itself, so restarting the broker (even if you could) wouldn't help.
You say that the broker isn't "servicing any requests". The "MQRA:DCF:allocation failure" error doesn't signify this, as the pool is in the Glassfish instance, not the broker.
The first thing I would suggest is to double-check that your code is closing JMS connections after use, even if an application error occurs (perhaps use finally{} blocks).
Or was there any prior error which might have led to this?
Nigel
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