There was a handful, I believe, in 2002. As you recall, the Canadian Forces were deployed in Kandahar Province in December 2005. From 2004 and 2005, Canada had a small force around Kabul. In 2002 they were involved in some counter-insurgency operations and Canada did detain some individuals. I think it's somewhere in the range of 12, and they were handed over to the American authorities.
On March 17th, 2010. See this statement in context.