I made some mistakes....
- Upgrade from BT5R1 to BT5R2 => OK
- Install Madwifi drivers with the BT5R1 guide =>> Failed

I followed all the steps but as the "make && make install" wasn't able to find te libraries, I typed the following:
ln -s /usr/src/linux-source- /lib/modules/3.2.6/build
I think it was a mistake since I'm on the new BT5R2 kernel and typing the directory that contains the old one.

Results: Lost of my wlan0 device and no more wifi connection.

Fixing: I removed all that was added by "echo"

New results: I get my wlan0 back and basic Wifi is now working.

Still some problems:
Since this bad installation, I still able to connect on AP (with or without protection), surf on internet, sniff paquets, use sslstrip, wireshark, ettercap and so on but when trying to cracking my own weak 64bit WEP key, it's quite impossible. Injection is hazardous and even with more than 200.000 (!!!!) IVS, still cannot get my WEP Key (It worked before)

My questions are::
1) How to clean up my mistakes?
2) How can I install Madwifi Drivers on BT5 R2 with the new kernel?

Thank you so much!