Product Canonical URL

I'm migrating a website from virtuemart.
There I have the products in multiple categories. Virtuemart has rel="canonical" tag in head, but I don't see that in eshop. I am woried that google will now se this as two separate urls and will treat that as a duplicate content...

Is there an option to make main category link canonical?

Thank you
Matija

Did you fix this?

Dear all,

I will implement this in the next version of EShop.

Sincerely, Giang

Happy to read. Looking forward for it.

OK Mark!

I just installed the latest version of Eshop and see the feature where you can indicate a main category and extra categories. I just don't see the expected result: the addition of rel="canonical" in the source code.
I do see <base href="url" /> but the URL stated here is the URL of the active page. I would expect references to the main product page on the extra category pages to indicate Google that the page is the same and only the main page should beindexed.