From IBM ajax tutorial:
When 0 is equal to 4
In the use case where multiple JavaScript functions use the same request object, checking for a ready state of 0 to ensure that the request object isn’t in use can still turn out to be problematic.Since readyState == 4 indicates a completed request, you’ll often find request objects that are not being used with their ready state still set at 4 — the data from the server was used, but nothing has occurred since then to reset the ready state.
There is a function that resets a request object called abort(), but it’s not really intended for this use. If you have to use multiple functions, it might be better to create and use a request object for each function rather than to share the object across multiple functions.
Tags: ajax, ajax multiple requests, ajax requests, multiple requests, request

yeah, but how about
the function which handle the onreadystatechange event ?
do we create multiple function too?
instead of sharing a function ?
thx before..
PS:coz you said that we must create
multiple request object(such as XMLHttpRequest)
Livan – Indonesia