If you're looking from PHP you would see no difference in cookie management between IE and FF. If such difference exists - browser simply does not satisfy corresponding RFC. IE sometimes working...
Mean of any data fields you client has is a human only. So universal script that uploads any data to any right can not be written:).
All you can - to try to write script that will upload it your...
It seems a bad idea to keep password in cookies: everybody can read corresponding file and get it. There is nothing in you code that browsers can process by different ways. So I see one possible...