vista business crash/bluescreen with wireless connections

Hi, as I told in object, this issue happens on two notebook (a vaio and a
toshiba) when I use wireless connection.
Both notebooks have vista business with sp1 and they are connected to a sbs
2003 domain server. In the same lan there are also two notebooks with xp pro
sp2 and they work correctly.
I have tried to disable wap and wep autentication on access point (dlink), I
tried to assign a fixed ip instead of dhcp. No results. After some minutes
of work in wireless mode they crash with blue screen of death. If I use
ethernet connection they work perfectly.
Wifi card drivers are up to date on both pc. Both pc are new and only office
suite is installed, no other software.
Any other suggestions?

Thank you


marco