Dr. Albert Mohler, president of Southern Baptist Seminary and an extremely gifted thinker and communicator has a page on smacking in NZ here:

http://www.albertmohler.com/radio_show.php?cdate=2009-08-21

New Zealand has voted on a referendum on their law against spanking. The verdict? Parents in New Zealand want the right to spank their children when they are in need of discipline. Scripture encourages parents to discipline their children for their own good. Spanking is not a form of violence towards children; it’s a blessing that, when done in love, teaches them difference between right and wrong.

Thinking Christians (oh, how I wish there were more of you) should listen regularly to this man.  He is one of the best imo!