Unknown filesystem type

[Bogle, David (SAIC)]

Hi

I have added a new harddrive /dev/hdb to mys RedHat 7.3 system.
I put 1 primary partition on it, 39GB, ext2 Linux filesystem. This was done
with fdisk.
I umounted the drive and ran parted on it. Things work fine i.e. print etc.
I wanted to add a 3-4 GB fat32 filesystem on it so i resized the original
ext2 filesystem and tried to create a fat32 partition (i have tried both
primary and extended).
It keeps reporting "unknown filesystem type" when i run an mkpartfs primary
fat32 startMB endMB (where these are real figures)

Any ideas as to why i am getting this message?

Thanks and Regards

David Bogle