Mark, Actually, WebSphere MQ isn't based on Geronimo or any other Java-type server like WAS or WBI; it's still C or C++. For a long time (since back in the mainframe days) it was MQSeries; they stuck it under the Websphere brand to make it seem more enterprisey. http://www-306.ibm.com/software/integration/wmq/index.html Cheers, -J