By default, Apple’s Leopard (OS 10.5) only allows Time Machine to backup to connected drives.
“Mindflux” posted a workaround to allow network drives to be used !
Run this from terminal and load up time machine to select your drive! You don’t need to hook the drive up to the Mac first, you dont have to go chowning files and all that nonsense.
Code:
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1
Even easier, someone wrote an automator script that does this for you.