diffrent services from same IP

hi, i have running a freeradius, all works fine... but now, i need to handle two diffrent services from the same IP in diffrent virtual server. in detail: i have a VPN server and one or more coova chilli systeme. all this freeradius clients will running on the same system (localhost) but if i load the client configs, it throws the error "Failed to add duplicate client". of course, all client will have the same IP, all client running under localhost. it is possible to handle this ? diffrent services/clients on the same IP ? greez & thx, volker...