That is a choice that DW offers, but will not be recognized by the bindings panel.
you can always change it back to email after using the binding in UE.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.