[CentOS] Problems installing Centos 3.4 & 4 using NFS + Kickstart

My hardware is Sun V65x servers, (6GB RAM/2xXeon3GHZ/36GB SCSI disk).
I have NFS repositories of Centos 3.1, Centos 3.4, Centos 4 & RedHat 9.0 
ISO distros set up. I use boot floppies for each o/s with the same 
kickstart file which is of course altered to point at the desired 
distro. With Centos 4 I have to use a boot CDROM, of course, rather than 
floppy disk.  I wish to set up servers with either Centos 3.4 or 4 
versions rather than RH9. Root disk partition is 24GB btw.

The kickstart boot works fine with RH9 & Centos 3.1. However it fails 
with Centos 3.4 & Centos 4 but in different ways:

Centos 3.4
========
The kickstart proceeds normally, formats the partitions & starts the  
install. However at 52% of the way through,  it aborts, always on the 
same file: "glibc-kernheaders-nnnn.rpm"
The fatal error message is non-specific & suggests that media is 
defective or disk space inadequate. I have checked the md5 sums of the 
ISOs & they agree with the download site ones. I have also extracted the 
"glibc-kernheaders-nnnn.rpm" from the ISO image #1 & compared its' md5 
sum with the same module from the /os/ directory on the download site & 
they also agree. I have also downloaded the ISOs again & they are the 
same md5s as the first set :-\

Centos4
=======
This install gets to the point at where it would normally try & mount up 
the CENTOS4 NFS repository which is on the same server as all the other 
distros (this runs RH9). It then goes into a loop whereby it keeps 
prompting for the name of the NFS server & the CENTOS directory,  where 
it would normally just mount it & proceed with the installation.

Anyone out there with similar experience & a working fix for this issue 
please ?

Les Oswald