Quick note on using fAircrack V0.49 with KP 50:

As per Estel's post, all you need to do is copy all the .ko files from the v0.2 drivers to ~/MyDocs/wl1251-maemo/binary/compat-wireless directory and just ignore the warning produced by fAircrack on the Monitor Tab. I have a working V0.50 (to match KP50 ), but I promised Estel to push out V0.50 via repositories, and I am not ready yet .

So, for all our noobs out there (assuming you already had a fully working fAircrack V0.49 or earlier for KP49 or earlier version on you N900):

1. Download the driver for KP50 as per pali's post. Thank the author for still supporting our device .
2. Extract in the directory the file was downloaded to3. Change to the compat-wireless subdirectory4. Copy all *.ko files to the correct directoryHint: Only need to type the first few letters of a directory or filename and then use the Tab button on the X Terminal screen to complete the rest of the word.

Have fun