context and multiple mib-instances

[jan-ivar.nymo____4tel.no]

how can I use the snmpv3 context(name) to differ between multiple
mib-instances in an agent?
It would be perfect if I could use the context as key in a routingtable that
describes what route
to take to find a specific instance of a mib-variable. But, what I can see
from the examples in 
agent++, allowed context's have to be predefined when initializing the
security constructs.

any suggestions would be greatly appreciated.
regards jan-ivar.nymo at 4tel.no