where is the startkde file of kde4

hello mailing-list, 
I have installed kde4 on the current freebsd. 

Now I want to start it but I don't find the start script in /usr/local/kde4/bin

I try the scripts kde4 kded4 kdeinit4 but I get always the error "$Display is Not Set" 

how can I set the display or start kde4?

- Robin Lehrmann