Thanks, I will give that a go.

It seems obvious looking at it now, but i really couldn't see the wood for the trees.

Many thanks. 

Thanks Rob. 

I have implemented a function wrapper to change namespaces before an operation and then reset it again afterwards, and it seems to work reasonable well.  As we are intending to insulate customers' data from each other with namespace allocation, it does seem to make sense to have a battery of QEWD instances with one running for each namespace, as it will reinforce the separation of services between customers.  This will be a topic for discussion with the rest of my team.