[otrs] A few questions on otrs' capabilities.

I want to install a trouble ticket manager program here but have a few questions I would appreciate some feedback: o Is there a way for the customer to keep track of a ticket through email? o Does otrs have to be on the same machine as the mail server that handles its messages or, say, it can check and download them like a normal user would? If so, what would happen if the link is severed? o If a help desk person wants to reply to customer, must she use the web interface to send a reply or can she user her normal mail client and her reply will (through cc: or whatever) be added to the ticket?