[otrs] list of queues for customer by default

I install OTRS 2.0.4 and create some users in it. for example, I create user "customer" and queue "internal", and want to this thing: when customer user log in and create new ticket, he cannot choose queue name in "for" filed (first drop-down list), instead it post his tickets in "internal" queue always. How can i do it? I try to include customer user & queue in one group (users), but no effect. what section of manual I must read ? %) -- Mike Lykov ISP Samtelecom, Administrator