Cannot access or ping worgroup computers protected wireless network

Hi, I unable to connect between two computers on a local home “workgroup” secured wireless network.
Machine (a) is running xp media centre 2002 sp2,
machine (b) is running xp home sp2.
Both machines nodes are set Node Types= Broadcast.
Network is wep enabled.
SYMPTOMS:

Both computer resides on a network.
? Both computer’s are a member of the workgroup.
? No firewall is enabled on either computer ( windows firewall disabled)
? The computers cannot ping each other (times out), they can ping the router.
? NetBIOS over TCP/IP functionality is enabled.
(Cannot view other workgroup computers on the network.)
All I was asked to do was make a printer on one p.c. available to the other on a clients home network! it’s got me baffled.