Have to keep repairing wireless commection

Hi
Have 6 Dell latitude d505 laptops with internal Dell Truemobile 1350
wireless cards with static IP address assigned and Win XP SP2 installed,
with Windows managing the wireless connection.
Access point is USR Wireless Turbo MultiFunction Access Point (USR015450),
128bit WEP with SSID broadcast enabled

Problem I'm seeing is that when laptops boot, they come up seeing the WAP
with strong signal. When laptop connection to local network attempted it
fails. If repair is done on wireless link, all is then fine till the next
reboot when the cycle repeats.

Has anyone any thoughts on this..it's driving me potty !!!

Ta
Mike