CentOS 5 :: Create A CentOS Based LiveCD That Mounts A NFS Share And Executes One Script?

I'm trying to create a CentOS based liveCD that mounts a NFS share and executes one script there. The NFS never mounts altough while logged I can mount it with the very same command that I use in the KS.

In the %post I have :

%post --log=/tmp/post.log --erroronfail
mkdir /mnt/nfs
mount -o nolock 10.23.1.1:/csc/RemoteHome /mnt/nfs

I added the --log in order to debug, but nothing is written in /tmp/post.log. I tried redirection on the mount command with >> /tmp/debug.log but this is not written. Maybe during the post sequence /tmp is RO ? Anyway, I tried with ifup lo, service portmap start in the %post, but doesnt change (I even have a service : command not found in the live cd creator output).

Here is the remainder of the KS :
lang en_US.UTF-8
keyboard us
timezone US/Eastern

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