Sorry if this is a dumb question, but what is the model you intend for
SNMP? Do you want each namespace to be its own virtual machine with
its own, separate MIB?

Ifindex's have to uniquely identify the interface (virtual or otherwise) 
to remote
queriers (not just local applications), so unless you pay the price of 
separating
all the SNMP MIBs per namespace too, it seems you'll need some way to
remap these for SNMP queries, right?

                                                +-DLS