I guess i found the anwer 
http://forum.mikrotik.com/t/vlans-via-bridge-working-but-still-confused/160676/3
" Any vlan associated with a bridge > must be identified with at least one interface on the bridge > in the /interface bridge vlan settings. "
So you CAN add the interfaces manually, but as long as one interface is added as tagged, the router will figure it out by itself..
Crazy stuff this Mikrotik Equipment 