Wayne Stallwood wrote: 
On Wed, 2008-05-07 at 11:19 +0100, Chris G wrote:

  
rdiff-backup only uses librsync at the very lowest level to work out
the minimum data transfer to update a file as far as I can see.

    
Ahh in my magical little oversimplified world it was just a wrapper for
rsync that added versioning :)

I've used rsnapshot, which is just a script that wraps around rsync and gives snapshots.
Two settings near the top: rsync_short_args and rsync_long_args
Any use?
Bill