This statement on Rockettheme tutorial is wrong in my case
"- Here is a much better tutorial (and visual) tutorial:
www.ostraining.com/blog/joomla/multi-lan...-sites-in-joomla-17/
BUT: they are wrong at point 9. of the tutorial as this one is also only valid for Joomla 1.6. But just start doing what is explained in the tutorial, except step 9."
I followed step 9 on OStraining tutorial and everything works just perfect now.