Try this.
Create two pages. One for the contact form and another to send another message. On the first Trigger it with Any Form Post, redirect to the second page and Trigger it with Before Page Loads and send the second message.
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.