No último comando aconteceram as seguintes coisas:
root@bt:/etc/init.d# ./networking restart
* Reconfiguring network interfaces... There is already a pid file /var/run/dhclient.wlan0.pid with pid 1571
killed old client process, removed PID file
Internet Systems Consortium DHCP Client V3.1.3
Copyright 2004-2009 Internet Systems Consortium.
All rights reserved.
For info, please visit
https://www.isc.org/software/dhcp/
Listening on LPF/wlan0/1c:65:9d:0c:71:76
Sending on LPF/wlan0/1c:65:9d:0c:71:76
Sending on Socket/fallback
Ignoring unknown interface eth0=eth0.
wpa_supplicant: WARNING: plaintext or ascii WPA key has 7 characters,
wpa_supplicant: it must have between 8 and 63 to be valid.
wpa_supplicant: If the WPA key is a 256-bit hexadecimal key, it must have
wpa_supplicant: exactly 64 characters.
Internet Systems Consortium DHCP Client V3.1.3
Copyright 2004-2009 Internet Systems Consortium.
All rights reserved.
For info, please visit
https://www.isc.org/software/dhcp/
Listening on LPF/wlan0/1c:65:9d:0c:71:76
Sending on LPF/wlan0/1c:65:9d:0c:71:76
Sending on Socket/fallback
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 8
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 7
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 12
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 10
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 4
No DHCPOFFERS received.
No working leases in persistent database - sleeping.
[ OK ]
Depois tentei dar refresh e mesmo assim não detecta nenhuma rede wireless... O que houve?