Description of problem:

Messages may be lost on connection close.

How reproducible:

Intermittent, frequency depends on details of application and execution environment.

Steps to Reproduce:

1. Publish a small message and close the connection immediately.
2. Verify that the message is queued.

Because the problem is intermittent, this must be done in a loop with enough
iterations to cause the problem to appear. The exact number of iterations
required depends on the details of the execution environment. One thousand
iterations is probably a good place to start.
  
Actual results:

Occasionally the connection will close before the message has been sent to the
broker.

Expected results:

The message should never be lost and always be enqueued.