I'm searching for a script that could put MT into sleep, or just put all interfaces off. This is important because occasionlly, on stormy weather, my wireless cards die...
Is there a way to succesfully do this?

Just disabling interface won't help. Detaching antenna cable from interfaces may help.

Yes, I was afraid of that answer because that isnt't solution for me. Access points are too far from me to do something like that. So, I only can prey that my cards won't go to junk jard...

your cards die just because the storm, or by electrical discharges?

i've never seen cards dying only because a heavy storm
if the problem is electrical discharges, you can put some protection near your antennas

hpe this helps you

IMHO,
it is better if you use some power surge protector, rather than make it "sleep".