Still having troubles with Dynamic Stamps

I have read countless articles and have tried to follow the steps as carefully as possible. Despite all that, my dynamic stamps aren't working.
 
It's just a simple stamp with a form field for the current date. The stamp appears in my Stamps drop down list but the JavaScript doesn't seem to work. The JavaScript date remains stuck as the stamp's creation date. I have copied/pasted JavaScript from template stamps which use the current date but still no success. Here is the script:
 
event.value = (new Date()).toString();
AFDate_FormatEx("mmm dd, yyyy");
 
I have spent many hours trying to debug this. Can someone please help? I would greatly appreciate it.
 
Windows XP Pro 32-bit
Acrobat 8 Pro v8.2.6