[otrs] Include ticket number in new tickets

Hello guys, can anybody tell me how I can add the ticketnumber of a new ticket into the signature of the ticket at the same moment I create a ticket? I tried the following tag: # But the result is just a --> "#- " In the subject the ticketnumber on new tickets is also included, so I think there must be a way, or not? Thanks for any help! Best regards, Yannick