[otrs] disable customer panel

Hi, We want to phase in the use of OTRS, starting by registering all requests manually ourselves. During this initial phase, we don't want to allow customers to create their own tickets using the GUI, whilst we do want to be able to continue tweaking, and configuring the system for customer use later. Where can I disable it, whilst still allowing me to configure it (and turn it back on occasionally, for testing). I'm hoping this can be done somewhere within sysconfig. Cheers! Marius