No, it doesn't make sense but I have a clue.
You also need to load the SCSI modules.
modprobe scsi_mod
modprobe sd_mod
You can use the lsmod command to verify the modules are loading.
Now you should see something with the cdrecord --scanbus command and
dmesg | grep sda
If you see any output your ready to go. To mount the drive
mount -t vfat /dev/sda4 /mnt/zip100.0
To umount the drive
umount /dev/sda4
Here is the how to:
http://en.tldp.org/HOWTO/ZIP-Drive.html#toc2