I wouldn't keep your fingers crossed for a speedy resolution. One of the agents I spoke with regarding this issue indicated that it was a known problem but not high on the priority list. Apperantly, this was a long-time problem on the America West website that got corrected not long before the relaunched site - and then subsequently the fix stopped working when the websites merged.

Frustrating - it's not only Canadian credit cards, but those from everywhere other than the US. Hard to call yourself an international airline when people who live in many of your destinations can't book your flights.