Is it possible to wardrive using an iBook with an airport extreme card? Does the airport extreme have an option where it can go in passive mode? I ask this question because the iBook does not have an PCI slot like the Powerbook does therefore, I couldn't put an Orinoco card which would have the option to go in passive mode.
Thank you.

You should be able to use an iBook with AirPort in passive mode with KisMAC.
Read more here!

Like solaris said you use KisMac a free WiFi search program, you activate it leave your iBook idle and it will keep looking and logging all Wifi hotspots it can find (It will also note the signal level and if it is password protected or not) - Also if you have any type of GPS it can stick these Wifi hotspots on a map for you! (Now thats neat).

It works with any Mac aswell.

Thank you for your replies,the only thing I was worried about is that the airport express not being as powerfull as an Orinoco card. It's preety cool how t swaps the Viha driver for your existing AirPort driver when the program starts, and automatically reinstalls the standard driver on exit.

I get great signal with my Airport Extreme card in my iBook goes really far.

I think KisMAC only supports active mode with Airport Extreme (it supports the old Airport card in passive mode though).

If you want passive mode, you can get a USB wireless adapter that has one of the supported chipsets.

Yea, you are right in the article it states that passive only works with airport and NOT airport extreme at the moment.

you may want to check out:

istumbler - http://www.istumbler.net/

or

macstumbler - http://www.macstumbler.com/

Macstumbler hasnt been updated in a while tho..

Have been on a few drives/walks with KisMac myself (using an Extreme card in Active mode) works very nicely. Would like to be able to use it in passive mode though.

Must say that iStumbler looks promising too, have yet to give it a real world test though

KisMAC works very well on my PowerBook. It is my program of choice for finding networks, and Ethereal under X11 for capturing packets. It took me a while to get it running but it was worth it.

I saw the demo of Kismac being run on an Powerbook, thats why I was talking about the PCI slot.