rules multiple uploads

Okkk, I get it now. So you could do this, or maybe you could use Javascript to set a name when the field's value is changed. Something like... (not tested)

Code:

<input type="text" onchange="changeName()" />

function changeName() {
  var inputValue = this.value;
  this.setAttribute("name", inputValue);
}

But you will probably need to remove spaces, special chars, etc... too.

So, maybe your solution is the simplest. I don't know :-)