Remove lines: 484-505 and then remove line 37.
That should do it. It looks like it isn't required anymore even for authorize.net.
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.