Yep, Canadian coins will stick to a magnet. Unlike US coins, which are made of a non-magnetic alloy, I believe Canadian coins are steel (not sure, but they WILL get caught on mech magnets).
We saw quite a few Canadian quarters on my route and in the airport. Canadians would jam the machines with their quarters so often that my boss had me remove the magnets entirely. Funny thing is, Minnesotan banks (at the time, anyway) treated the Canadian quarter as 25c US, oddly enough.
Magnet removal on most models of mechs is pretty simple and self explanitory. Some are kept in place with bendable tabs, screws, or whatever. Some you have to snap a plastic retainer. No matter, just remove the magnets and stick them to the refridgerator. The mech will operate as normal (even with quarters from north of the border)
APf