this is because your "MyMDBQcf" is not XA capable, in other words it is not an instance of javax.jms.XAConnectionFactory.
Did you perform the following step that is mentioned in the doc
"The jndiAPI does not ( or iam not aware of) allow bindings of type XAQueueConnectionFactory, so please change the "Factory Type" of inboundXAQCF and outboundXAQCF to "XAQueueConnectionFactory" through the Sonic MQ admin console. The console can be started using the command MQ7.0/bin/startmc.sh"
Did you change the type of MyMDBQcf to XAQueueConnectionFactory
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