I'm running multiple SUMO simulations in parallel using TraCI.
Every so often one will fail with the message
Error: tcpip::Socket::accept() Unable to create listening socket: Address already in use
Quitting (on error).
I haven't found anyway to set the address to use on the configuration list at http://sumo.dlr.de/wiki/SUMO
I figure if I can set each instances address manually I should be able to avoid this.
The answer is right on the page you mention. The option --remote-port specifies the port number, so something like
sumo --remote-port 54323 -c my.sumocfg
should do the trick. Of course you need to give the same port when connecting from your traci client.