Wirless disconnect when swith user

Hi I have Inspiron 6400 with Windows XP Home and I have enabled 'Use Fast User Switching' option . When I log on as User1 (Admin) and try to switch to User 2 (Admin) by 'Switch User' (not log off) my wireless disconnect and connect again. .  The problem is because when card disconnect and connect again User1 applications can not use internet. I was trying different things like: changing between Intel and Windows wireless manager, setting up new network etc Disconnection happening in moment when User2 is login in (when I am on blue screen with login options wireless is working fine - eg online radio is working for hours). Thx for help