I have setup my website to use canonical urls on each page to point to the page i wish Google to refer to.

At the moment, my non-www domain name is not redirected to www domain. Is this required if i have setup the canonical urls?

This is the tag i have on my index.php page

rel="canonical" href="http://www.mydomain.com.au" />

If i browse to http://mydomain.com.au should the link juice pass to http://www.armourbackups.com.au?

Will this solve duplicate content problems?

Thanks