testing remote hosts with different source address

Hello everyone,
I am using Hobbitmon 4.2 and I would like to set up a system with
multiple IP addresses on network interface so that I can perform test to
some hosts through an IP address and other tests through another IP
address, and  so  on with multiple address aliases.

The hobbitping has a --source option but bbtest-net does not.

I have thought of using the LOCATION tag in  bb-hosts and have multiple
instances of bbtest-net in hobbitlaunch.cfg but I do not find a way to
have packets exit from the system with a different source address for
all TCP tests as well as ping.

Has anyone ever done such a setup?

thank you.
Lorenzo Chiavacci