Able to save Tickets as Drafts

Sometimes bug tickets take a while to get fully filled out and currently there is no way to save these to work on them over a period of time. Also, we found that when we accept a phone call, if we are working on submitting a ticket, the ticket disappears and we have to start all over. It would be great to be able to have these tucked away in a Draft where we can open it up and finish it up after the call.