First remove the package you've installed.
Then install a 11.0 package.
You'll find a 11.0 package at this location:
Even if the site is in italian language, you can read that there are dependencies (dependenze) that are also available on the site (http://www.slacky.it)
. Just do a search with the box on the top left of the page.
Install the dependencies first in the order listed and everything should be fine.
I use a lot of packages from this site and if you follow the dependencies as described you'll have no surprise (except that it works out of the box)