KVM in RHEL5.4 doesn't support VHD??

[tsk]

hi folks,

    I am using KVM of RHEL 5.4 ,  but i can't install a VM into a vhd format
image:

root at SS01 # /usr/bin/qemu-img create -f vpc
/guest/SS_test/image/redhat-5.3-64.vpc 51200M
Formatting '/guest/SS_test/image/redhat-5.3-64.vpc', fmt=vpc, size=52428800
kB
qemu-img: Formatting or formatting option not supported for file format
'vpc'

But the help info of qemu-img said:
Supported format: parallels qcow2 vvfat vpc bochs dmg cloop vmdk qcow cow
host_device raw


Who can tell me anything about this?
what should i do to install a VM into a vhd format image

3ks!

TSK