How do I disable multipath in RHEL 6.3?

Issue

# /etc/init.d/PowerPath start
Starting PowerPath: Aborting PowerPath start since DM-Multipath is active. Refer to PowerPath for Linux Installation and Administration Guide for more information
 failed

• We disabled the native multipathing (multipathd service), inserted "nompath" to the grub.conf file & blacklisted the devices in the multipath.conf file but still its getting activated during boot up as shown below.

# chkconfig --list multipathd
multipathd      0:off   1:off   2:off   3:off   4:off   5:off   6:off
# grep nompath /etc/grub.conf
        kernel /vmlinuz-2.6.32-279.el6.x86_64 ro root=/dev/mapper/vg_root-LogVol00 rd_NO_LUKS LANG=en_US.UTF-8 rd_LVM_LV=vg_root/LogVol00 rd_NO_MD rd_LVM_LV=vg_root/LogVol04 SYSFONT=latarcyrheb-sun16 crashkernel=auto  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM nompath rhgb quiet

# cat /etc/multipath.conf
# multipath.conf written by anaconda

defaults {
        user_friendly_names yes
}
blacklist {
         devnode "*"
}
# multipath -l
mpatha (36006016003502d0078c87865d6b7e211) dm-0 ,
size=20G features='0' hwhandler='1 emc' wp=rw
|-+- policy='round-robin 0' prio=0 status=active
| |- #:#:#:# - #:# active undef running
| `- #:#:#:# - #:# active undef running
`-+- policy='round-robin 0' prio=0 status=enabled
  |- #:#:#:# - #:# active undef running
  `- #:#:#:# - #:# active undef running