I don't know if somebody already figured this out, but I couldn't find it on this site.
I wanted to connect one black-white pinter and one color printer to my router.
The first printer (black-white) is connected to router and is identified in the web. To print from this printer with the oleg firmware I used the regular Oleg tutorial to connect my printer.
http://oleg.wl500g.info/printing/
Now lets hookup number two.
Connect the second printer and reboot you're system. look in the web interface and make sure that you're thirst printer is identified. If not switch the USB's and try again. It toke me some time to figure out in witch order the USB poorts are read, but there is logic...
Connect to you're router with putty and log in.
Past the following line and
Code:
echo "p910nd -f /dev/usb/lp1 1" >> /usr/local/sbin/post-boot
Reboot you're system with
Code:
flashfs save && flashfs commit && flashfs enable && reboot
Now install you're second printer. But instead of port number 9100 change it in 9101. Proceed as normal and you should have a working second printer.
This is how it worked for me. Unfortunately I'm not so good in this so if there are any problems I will try to help but I don't know how helful I can be.