Recently we experienced a strange issue on one of our clients’ Weblogic Integration domain. From Weblogic Integration console, when we were trying to purge process data, it was always showing a RUNNING state and didn’t allow us to trigger the purge process. After observing the phenomenon for several weeks, we realised the issue. The root cause for the change in behaviour is a deployment change for MDBs between 8.1 and 9.x. Since 9.x a MDB deployed to a cluster connects to a physical queue that resides on a remote server in the cluster. This was different in 8.1. Here the MDB connected to local queues only.