Make sure you really have a SCSI interface on the Zip drive. Is there the little SCSI logo above the port or a pictogram of a printer?
Iomega made them in several configurations and both SCSI and parallel port drives have a DB-25 interface on them. The parallel port version doesn't have a SCSI ID switch, where as the SCSI ones do.
See this page for more info: http://www.iomega.com/europe/support/en ... 1382e.html
Fairlight IIx (Mid-Life Crisis - cheaper than a Corvette!)
Roland JP-8, D-50, S-50, S-550(2x), S-760(2x), JX-3P, JD-800
EII, Emax II, Minimoog, ARP 2600, P-5 Rev.1 (broken...), Pro-One, Crumar Performer, K1m, K5m, MS-2000B, Virus KC, a few other things.