Our first peacekeeping mission in Korea—in fact, it was our first Canadian peacekeeping mission—was in 1949 when we sent somebody to supervise the elections. That's where you get the 1949. You are quite correct that an armistice was signed in 1953; a peace treaty has never been signed. Technically, North and South Korea are at war.
On March 6th, 2008. See this statement in context.