Wireless network not talking to winnt

I have installed a wireless network. I have other
desktops in my network (win2000 and winnt40).

The winnt40 and win2000 desktops can see each other. The
win2000 and winXP can see each. But, the winnt40 and
winxp cannot see each other on the network.

Can anyone help me determine why this is happening? I
tried everything I could think of to correct this
problem ???

Thanks.