Invalid Token when pressing "Login"

Hello,

I'm using Komento platorm integrated with K2 Articles Component.

The problem i have is that whenever i press on Login button i get Invalid Token error Message.

You can see it here:
http://4drivers.gr/respect/item/2112-smart.html

(Scroll to bottom and use everything for username & password and press the "Red Button" because you'll probably won't understand the language).

I already tried clearing cache on browser & server, disabled system-cache plugin, cleared cookies.

I tried to login with the Joomla's default login module or via this link: http://4drivers.gr/component/users/?view=login and i can login normally.

The problem is only at Komento's login form.

Thanks in advance,
George