Stupid mkfs question

["Jason Cole" <colejp@xxxxxxxxxxx>]

I know this will sound stupid but,

I have just installed fedora core 2, and installed xfsprogs

thats ok,

now I want to create a XFS partition, I have about 20g free on my drive.

(note: /dev/hda1 - 3 are used)

so typicaly (as far I can read) I do mkfs -t xfs /dev/hda4

but get

mkfs.xfs: can not open /dev/hda4: can't find device or address

so my question is how do i make the device or partion /dev/hda4


thank's

Jason