[H] windows wireless

[Winterlight]

I am working on a circa 2004 T53 Thinkpad that is still pretty much 
stock. It is running XP2 PRO fully patched. Everything is fine except 
an issue has developed with the wireless connection. It works but 
won't work with encrypted networks. I can set it up with a key, and 
it sees the network, tries to connect, but fails. Previously, it did 
connect to a secure network. I personally have a older T23 Thinkpad 
that will connect to that same network... so it isn't the router / 
WAP, which by the way is using WPA2 Personal.

In addition, in the Windows XP <Wireless Network Properties 
window>>>>Wireless Networks tab>>> has a check box for
Let Windows manage my wireless network .....and this keeps coming 
unchecked with each reboot.

The first thing I did was to remove any vestige of the annoying IBM 
wireless utility, so that windows XP would manage this. Then I got 
the most recent wireless adaptor drivers from IBM = May 2007 and 
installed it. But I am still having the same problems.

Any body have any ideas?