kdump failing to start on rhel

Hi,

I followed instructions to configure kdump, but I am not able to start it on RHEL 6.2 server.
Can somebody check and help, what I missed here
Code:# cat /boot/grub/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/rootvg-root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
#splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux (2.6.32-220.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-220.el6.x86_64 ro root=/dev/mapper/rootvg-root rd_NO_LUKS LANG=en_US.UTF-8 nomodeset rhgb crashkernel=256M quiet rd_LVM_LV=rootvg/root rd_NO_MD quiet SYSFONT=latarcyrheb-sun16 rhgb crashkernel=256M rd_LVM_LV=rootvg/swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM
initrd /initramfs-2.6.32-220.el6.x86_64.img
#
# cat /proc/cmdline
ro root=/dev/mapper/rootvg-root rd_NO_LUKS LANG=en_US.UTF-8 nomodeset rhgb crashkernel=auto quiet rd_LVM_LV=rootvg/root rd_NO_MD quiet SYSFONT=latarcyrheb-sun16 rhgb rd_LVM_LV=rootvg/swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM
#
# grep -v ^# /etc/kdump.conf

path /var/crash
core_collector makedumpfile -c --message-level 1 -d 31
#
# service kdump start
Starting kdump: [FAILED]
#
# cat /var/log/messages | grep dump | tail -5
Mar 4 16:20:52 rhel-server-22 kdump: No crashkernel parameter specified for running kernel
Mar 4 16:49:08 rhel-server-22 kdump: No crashkernel parameter specified for running kernel
Mar 4 16:49:12 rhel-server-22 kdump: No crashkernel parameter specified for running kernel
Mar 4 16:52:49 rhel-server-22 kdump: No crashkernel parameter specified for running kernel
Mar 4 17:06:47 rhel-server-22 kdump: No crashkernel parameter specified for running kernel
#Thanks