From memory, so forgive lapses. The ability to use HFS+ volumes with a 68K Mac is dependent on three things:

1. Ability to boot Mac OS 8.1 or later

2. Hard disk partition size (4GB for 68K Macs running Mac OS 8.1?)

3. Existence of HFS+ wrapper -- OS X does not write the wrapper

None of which I believe addresses the original problem.

Hola, Leosadvs. How are you connecting your SCSI drives to your G4? Are you using a physical SCSI connection or a network AppeShare connection?