Well that was what I thought, Boxing day just being a very english celebration. I know, Ill search wikipedia....
EDIT: They say and I quote:
'Boxing Day, December 26th, is a public holiday in the United Kingdom, Canada, New Zealand, Australia (excluding South Australia), and countries in the Commonwealth of Nations with a mainly Christian population. It is based on the tradition of giving gifts to the less fortunate members of society. Contemporary Boxing Day in many countries is now a "shopping holiday" associated with after-Christmas sales.
The day is historically the British name for St Stephen's Day, 26 December, which is a public holiday in many countries with predominantly Christian populations. In the Eastern Orthodox Church, St Stephen's Day is celebrated on the 27th of December, although in Greece Boxing Day (Synaxis Theotokou, Σύναξις Θεοτόκου) is also celebrated as a public holiday on the 26th of December.[citation needed] However, unlike St Stephen's Day, Boxing Day is not always on 26 December (see below).
It is usually celebrated on the 26th of December, the day after Christmas Day[1][2]; however, its associated public holiday can be moved to the next weekday if the 26th of December is a Saturday or Sunday. The movement of Boxing Day varies between countries.'
So basically members of the commonwealth, except south australia wierdly.