Please ignore my previous post.
I have managed to solve my problem. Apparently Network Manager in karmic only allows your wifi to activate upon logging in to Gnome or KDE (not sure if this is a bug or what).
I solved the problem by installing wicd (which replaces network manager) and configuring the wifi to automatically start. When the machine rebooted, the wifi was up even before I logged into Gnome.
Hope this helps you as well.