Use Time Machine (OS X) with a (samba) Network Drive

sudo defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

...but cf. http://pastebin.com/f47499d34 after update to 10.5.2.

references:

1. http://www.2putts4par.com/2007/11/10/use-time-machine-with-a-network-drive/