I have solved the following problem. See below:

I have been having difficulty using VMware converter 5.5.3 and a RHEL 5.5 VM to ESXi 5.5. The VM panics on boot with:

...
Loading dm-raid45.ko module
device-mapper: dm-raid45: initialized v0.25941
Waiting for driver initialization.
Scanning and configuring dmraid supported devices
Trying to resume from /dev/sda2
No suspend signature on swap, not resuming.
Creating root device.
Mounting root filesystem.
EXT3-fs: Unrecognized mount option "auto" or missing value
mount: error mounting /dev/root on /sysroot as ext3: Invalid argument
...

The fstab of both the original and VM:

LABEL=/ / ext3 rw,suid,dev,exec,auto,nouser,async,acl 1 1
LABEL=/tmp /tmp ext3 defaults 1 2
LABEL=/var/log /var/log ext3 defaults 1 2
LABEL=/boot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
/dev/sda2 swap swap defaults 0 0
/dev/sdb1 /media/usb auto auto,user,dev 0 0
/dev/scd0 /media/cdrom auto auto,user,dev 0 0

I tried booting into Linux rescue and removing the auto and later some other options and had the same error. I commented out the last 3 lines and got the same error. I tried mkinitrd and got the same error.

fdisk -l

Disk /dev/sda: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 535 4192965 82 Linux swap / Solaris
/dev/sda3 536 1057 4192965 83 Linux
/dev/sda4 1058 30401 235705680 f W95 Ext'd (LBA)
/dev/sda5 1058 1579 4192933+ 83 Linux
/dev/sda6 1580 30401 231512683+ 83 Linux

Disk /dev/sdb: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 1 30401 244195968+ fb VMware VMFS

On VM the /dev/sda1 ends one block later and everything from there down is one block greater and messages about partition not ending on cylinder boundary

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/sda6
# initrd /initrd-version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
password --md5 $1$0QwW3Duc$TcVz7ikeZduwS62xY5Z1w.
title Red Hat Enterprise Linux Server (2.6.18-194.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-194.el5 ro root=LABEL=/ vga=792
initrd /initrd-2.6.18-194.el5.img

The VM had "root=/dev/sda6 vga=normal" so I edited that and had the same failure.

When Linux rescue boots, in dmesg I see:

...
(6)device-mapper: dm-raid45: initialized v0.25941
(4)GFS2 (built Jan 27 2010 18:15:27) installed
(6)Lock_Nolock (built Jan 27 2010 18:15:34) installed
(6)device-mapper: multipath: version 1.0.5 loaded
...

I am out of things to try. Any suggestions?

--------------------------------------

SOLUTION:

1. Change Hard Disk 1 Virtual Device note from SCSI controller 0 to SATA controller 0
2. Boot into Linux Rescue and rename the initrd...img.old.0 to initrd...img

This worked for two physical servers. The third seems to be using software RAID so I might be out of luck on that