phranque - 3:37 am on Aug 23, 2013 (gmt 0)
when you do an nslookup of www.example.ca does it return the correct IP address?
does the server on that IP address have a virtual host configured for that hostname?
if i had to guess your server is configured to accept requests for wildcard subdomains and the default server is getting these requests.
you should see one of the following somewhere in your server config: