I have been trying to use my zip drive on FC 4, however I have ran into a few problems. Let me explain the symptoms and attempted dignostics:
Symptom:
Upon insertion of zip disk and typing the following command:
# mount -t vfat /dev/hdb /media/floppy
I get the following response:
mount: wrong fs type, bad option, bad superblock on /dev/hdb,
missing codepage or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
Attempted dignostic:
- Formate zip to Fat16 (first tried Fat32)
- Tried new zip disk formated to Fat16
- checked kernel .config to ensure vfat was being loaded

Any help would be appreciated

An already formated Zip disk uses partition 4.
Try:
mount -t vfat /dev/hdb4 /media/floppy

I do not have an hdb4 in my /dev dir. here is the output of my dmesg | tail:

[root@u /]# dmesg | tail
NTFS-fs error (device hdb): read_ntfs_boot_sector(): Mount option errors=recover not used. Aborting without trying to recover.
NTFS-fs error (device hdb): ntfs_fill_super(): Not an NTFS volume.
hdb: The disk reports a capacity of 250640384 bytes, but the drive only handles 250609664
hdb: hdb1
hdb: The disk reports a capacity of 250640384 bytes, but the drive only handles 250609664
hdb: hdb1
FAT: bogus number of reserved sectors
VFS: Can't find a valid FAT filesystem on dev hdb.
hdb: The disk reports a capacity of 250640384 bytes, but the drive only handles 250609664
hdb: hdb1

Have you tried a new Zip disk. They are already formated and use /dev/hdb4.
On the disks you reformated, did you create a partition?

A zip disk needs to be formatted even though it has been already formatted. You can add a primary partition with a partition type b for FAT32 or type 83 for Linux filesystems. All zip drives will default to /dev/hdX4 for the zip disk when you first insert it. There is no reason why Iomega picked this.

Why? Except for when I wanted a linux filesystem or want to experiment I've never had to reformat a Jaz or Zip disk. I've never had an issue with linux, Dos or windows reading the preformated disks.

I believe it is a compatibility with a MAC but don't know for sure.

The factory does not always format disks properly, so the disk will seem that it does not work. Always get in habit of formating zip disks, jaz disks, usb disks, and floppy disks.

I do not think to make it compatible with MAC. I think Iomega thought that extended partitions will make the drive come last instead of becoming before extra hard drives.

Did you ever get your zip disk to mount? If not, how is it connected to your PC. (e.g. mine is a scsi, but there are ide ones also.) If it is a scsi you won't find it at /dev/hdb4, but it should be at /dev/sdb4 or /dev/sda4 if it is the first scsi device. If you fdisk and reformat it in linux you can choose what partition it uses, so it could be at /dev/sda1 if that was what you chose. If you have already solved your problem, then just ignore my post with my apologies. (the thread is a bit old, but I didn't see where you say you have it solved so I thought...)