[Plugin: Like This] How to "Unlike"

Excellent plugin, everything works great!
But how to “unlike” a certain post? If i click on the link it says “1 person likes this” but if i click on the link again it doesn’t work like on Facebook, where it reverts your “like”.

Am i doing something wrong or this is how the plugin is supposed to work?

Thanks,
Ciprian

http://wordpress.org/extend/plugins/roses-like-this/