Problem Connecting a Inspiron M700 to a Netgear WGT624

I just purchased a Dell Inspiron M700 and we have had a Netgear WGT624 wireless router in our office which worked fine for over 6 months.

 

I shut off our WEP key and was able to connect the Dell Inspiron no problem to the network.  However, as soon as I turn the WEP key back on - every other non-Centrino (desktops w/ wireless cardsw in them) connected fine except the Dell M700.  I enter the WEP key when prompted - it appears to accept the key, but it keeps saying "acquiring address" - and it times out.  It can't connect.  I called NetGear and they say no known problem, but yet I see tons of stuff on the Internet about this issue but can't figure out a solution.  Any help is greatly appreciated.