G4 second drive "unsupported"

[Dale Hoffman]

A friend just called me with a problem installing a second internal 
hard drive in his G4 Sawtooth. He can't get it to initialize - Drive 
Setup says it is "unsupported".

He says the drive is an ATAPI 80GB Western Digital, but I've never 
heard of an ATAPI fixed drive. I'm thinking he may have misplaced the 
jumpers designating Master Slave, but I won't know until I visit 
tomorrow. Any other ideas?

DaleH