I have a SDP setup that we have been using for about 3 years now.  I'm using version 7508.

My users will sometimes email our SDP's email address and that will put in a new ticket if there is not one already.  Is there a way to prevent this?  I still want them to be able to reply to emails within a current open ticket, but I don't want a new one created.  This might be a little too much to ask, but it would be nice.  I am constantly having to tell people not to submit work orders by emailing the system.  They need to use the web site.

Ideas?