Apple Mac OS X Time Machine over NFS (10.5 or greater)

Create a Sparebundle to copy to your NFS/SMB/AFP volume
hdiutil create -size $SIZEg -fs HFS+J -type SPARSEBUNDLE -volname "Backup of $MACHINENAME" $MACHINENAME_$MACADDRESS.sparsebundle
Use ifconfig and sub in your $MACHINENAME_$MAC_ADRESS into the sparsebundle filename - Remove the ':' chars
e.g. 0018b31184dd
Use hostname to get your machines hostname - Don't use fqdn
Size can be adjusted at a later date if required - g = gigabytes
Copy the budle to the nfs volume
cp -rp $MACHINENAME_$MACADDRESS.sparsebundle /Path/to/nfs
Run the defaults command to turn on timemachine for unsupported volumes support (As normal user - don't sudo)
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1
Now go to your System Prefrences and choose time machine
Choose your NFS/SMB/AFP volume as the timemachine disc