How to auto add in pdf filename (shown in footer) by using Java Script?

Question

In order to have nice tracking a document, I want to print the file name as a header or footer when printing the documents. 
How can this be done?  
Found a perfectly nice post related to same issue
 http://forums.adobe.com/thread/302996 
 (Many thanks on every contribuitors inside that posts)  
 In the above post,  found that ##Reinhard had shared some well nice scripts for "enable to put in filename in the footer for every document, just by 1 simple click in each documents"  
For the time being, 
if i would like to generate a script that allowing 
1) Only adding / showning the pdf filename in the footer
2) Auto Run/Execute on this script for all documents, which means without any click but it will auto showing the "filename at footer" when any document opening.  
Hope any experts can give a help on this.   
PS: Currently using Adobe Acrobat 10 & Reader 11 // OS = Windows 7 
Many thanks ^^

Answer 1

My code for above method is Floor #2
var FileNM = this.documentFileName;
for (var p = 0; p < this.numPages; p++)
var fd = this.addField("xftDate", "text", p, [30,15, 290,30]);
fd.textSize=5; fd.value = " (" + FileNM +")";
It works for me & my PC, however I unable to applied same things into a JavaScript.js file
Hope any experts could help and advice.
Many thanks.