PXE Kickstart not happening

We have a lab where installation is done through PXE . The installation always run fine usually but suddenly we are getting the below mentioned error

any idea whats happening ?

==quote==
| Erros parsing Kickstart Config |
The following error was found while parsing your kickstart configuration :
The following error occured on line 32 of the kickstart file :
Specified nonexistent disk cciss/c0d0 in clearpart command
Reboot
==unquote==
can anyone tell me whats happening and how to trouble shoot this issue .

---------- Post updated at 06:56 AM ---------- Previous update was at 06:41 AM ----------

Hi folkz

I seem to have resolved it by using the following help .
I used LUN's in my case .
HP Proliants, the RAID controller disks show up
as /dev/cciss/c0d0, c0d0, etc. /dev/sda is the first SAN LUN and I want
Anaconda to just completely disregard it.

I mentioned device scsi cciss in kickstart and it worked fine .