I would not be able to tell by looking at the code.
one thing to note:
a version 2 cart can be edited with eCart 3.
a version 2 or 3 cart can not be edited using version 4 or 5.
a version 4 cart can be edited with eCart 5.
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.