Connect to Network without assign IP address

[Carlos Patricio Amigo Haering]

Hi everybody,

I'm working with bridging and virtual ethernet interfaces (veth). So, I 
want to connect wlan0 to a AP without assign it a IP. How can I do that? 
I tried in wpa_cli uncessfully:

> add network
0
> set_network 0 ssid "OF"
> set_network 0 psk "pass"

- I'm using Ubuntu 12.10 and wpa_supplicant v1.0
- The AP doesn't have dhcp server.


Thanks in advance.

Regards.