[iBook] WEP password

[Jim Shimozawa]

I have a friend with a G4 and a G4 PB both connected via Ethernet  
cable to a DLink router.
When I try to join its network with my Airport installed G3/700   
iBook, I am asked to enter a WEP password.
My friend does not remember it, and the person who helped him is no  
longer available.

Is there a way find out what it is?
If this is not feasible, how do I reset it?
Anyone?

TIA

Jim