Problem: Multiple Wireless Networks with same name

I work in a pretty dense down town area, and have a constant problem with my wireless that I think is the result. My work has multiple networks with the same name, but it seems that my system can't tell the difference between them! When one of the networks goes out, I cannot join another of the same network with the same name.

For example, my PC spots all three of the networks with the name ABC, and identifies them via their base station ID. However, when I try to select the network to join on my MacBook, it only shows one network ABC. I tried using a bit of third party software to help me connect to these other networks, but each time I tell it to connect to a different base station, it always connects to the same one. Problem being.... that base station is on the fritz, and has no DSN configuration at the moment!

Any idea how to work around this?