preserving data on partition

[Haber, Michael]

Hi,

I'm trying to install fai on a machine that already contains ms windows.
The docs say:
"It is possible to preserve the size of a partition or additionally to preserve the existing data on this partition."
I can't see where it says how to preserve the data.

My disk config looks like:

disk_config hda
#our windows partition
primary  -              preserve1                                           
#our linux partitions. /home is on nfs
primary  /              7000                  rw,errors=remount-ro ;lazyfomat
logical  swap           300

It seem that the partition size for hda1 is kept ok but the data (windows) is lost. How do I preserve the size _and_ data?
thanks
Mike