Namespaces in MEINT Workflow Handler Parameters

I have an incoming message that has namespaces in the tags. When I attempt use a valid path with the namespaces as an identifier nothing is returned and the identifier field in the Queue Monitor is blank.

This is the path I have entered in the workflow:

plant="200";identifier=concat(/soapenv:ZME_WC_REFRESH/soapenv:Body/ns2:UserChangeRequest_sync/ns2:SiteRef/ns2:Site,'-', /soapenv:ZME_WC_REFRESH/soapenv:Body/ns2:UserChangeRequest_sync/ns2:User/ns2:UserId)

And this is the result I get in the queue monitor.

Is there something specific we need to do to handle those namespaces or are they just not supported?

We are using MII 12.2.3 and ME 6.0.4