Unfortunately there are some issues where the shutdown did not wait correct for every other (needed) subsystem, so it can happen that a resource is already removed but needed.
This should be solved with the 'graceful' shutdown feature of EAP7 / WildFly.
Note that you need to shutdown with a timeout to enable that feature, otherwise the shutdown behave the same as EAP6/AS7.
Could you try this (EAP7 Beta is available)?
Thank you for your reply.
Unfortunately I am not in a position to upgrade currently but I beleive that I have found a work around using JBoss-cli to stop messages being delivered to the MDBs. This has, for the moment resolved the issue.
I will endeavour to test with a newer version of JBoss but I feel that it will involve some "fighting" with the standalone configuration and deployment structure of my application.