port 443
proto tcp-server
These directives makes openvpn listen on all interfaces, so on both adapters in your machine.
It's, i guess, the same as on my vps as you can connect on both my ip-addresses. But are you sure the second ip-address is a seperate NIC? I have an eth0 and eth0:1 for the different IP-addresses.
On the clientside you can issue:
remote-random
remote ip-address1 443
remote ip-address2 443
as a kind of load-balancing and therefore use both ip-addresses