[otrs] ITSM - multiple customers

Hi All, We are using OTRS for a couple of years dealing with IT problems at our customers networks and server's rooms - it's just doing what is designed for :). Now we would like to implement ITSM in our system for us and our customers. But I think (please correct me if I'm wrong) there is no support for multiple customers in ITSM? No separate catalogs, CMDB, customers permissions etc? Just one big ITSM system that everyone can access (of course if he/she is in one of itsm groups)? Best Regards, Aleksander Walesa POLAND