Memory leak in python client - unacked messages kept when no accept is necessary

We have found with python-qpid-0.22 that you have to acknowledge all messages received, even if you have subscribed using mode:browse (where ack does not apply) or even if you have subscribed to an unreliable topic exchange (where ack is not needed).

In these cases, if you don't acknowledge the messages received, memory is leaked, due to the accumulation of messages in an internal unacked list at the client.

More information at this qpid-users mailing list thread:
http://qpid.2158936.n2.nabble.com/Use-of-mode-browse-and-session-acknowledge-in-topic-exchanges-td7600571.html#a7600642