Envoy Message Queuing Connector is available from Envoy Technologies.
Notes:
The machine hosting MQC must have MSMQ installed on it first.
The machine hosting MQC must be part of a domain, and cannot be a workgroup PC. It installs, but it does not work.
The Envoy Message Queueing product was formerly owned by Level8 (http://www.level8.com). It has previously been named Falcon and Geneva MQ. Refer to the Envoy Technologies website http://www.envoytech.com for more information.