After recompiling a new kernel on CentOS 6.3, using the same kernel I have been using on several other machines, I am getting a kernel panic on two machines.

I get the following when trying to boot:

drivers/rtc/hctosys.c: unable to open rtc device (rtc0) (flashes this before displaying the panic below)

not syncing: Attempted to kill init! exitcode=0x00000100

Pid: 1, comm: init Not tainted etc...

I have been trying to figure out what is going on, and am having trouble doing so, and feel I have exhausted all of my options here. Any help would be appreciated.

My grub.conf:

default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (3.4.18-rt29)
        root (hd0,0)
        kernel /vmlinuz-3.4.18-rt29 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup/lv_root  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet panic=5
        initrd /initramfs-3.4.18-rt29.img
title CentOS (2.6.32-279.14.1.el6.x86_64)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-279.14.1.el6.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup/lv_root  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet panic=5
        initrd /initramfs-2.6.32-279.14.1.el6.x86_64.img

Any help or guidance would be greatly appreciated.