multiple IP-addresses for one VPN-Client? (2 or more)

tspf

I have a situation where it is necessary, that the OpenVPN-Client has multiple ip-addresses assigned to its TUN-interface:

e.g.
(Windows-Client) TUN:
192.168.0.3 /24
192.168.2.3 /24
192.169.1.3 /24

I tried the "--ifconfig-push" and "ifconfig" directives but only one address is assigned to my TUN device. Is there any way to achieve this using TUN (Layer 3)?

I think when using a TAP device it is not a great challenge. But i need to do some special routing and firewalling on the server side and send the traffic to the appropriate subnet and the current setup makes extensive use of TUN and routing.