hm.. well the problem is not in vistumbler anymore.. vistumbler is working fine, except it doesnt show channel information and mac adresses.
but thats not the problem, those i could find out with my mobilephone too.
the problem appears when i try to use airodump. it just says "no suitable devices found" - so i googled a lot, read tuts, tips and found in several forums where is mentioned that this card does not support monitor mode. well under linux it worked once, but crashed quite often.
maybe this is also not the right forum for questions like this, but it was where i had most hope for an good answer

or could i catch packets with vistumbler too? as far as i can see its not a program like that, is it?
sorry for the late answer, but thanks for your fast one
regards, dlp