I was finally able to get my wifi working with the following commands

iwconfig wlan0 essid XXXXX
iwconfig wlan0 key XXXXXX
iwconfig wlan0 mode Managed
iwconfig wlan0 channel 6
ifconfig wilan0 up
iwconfig wlan0 ap any
pump -i wlan0

This has to be run as root so su before. Note ifconfig instead of iwconfig on 5th command. Replace XXXX's with your values. Iwlist is a good utility to help see where you are.

Neeraj