Weird Issue with IE6 regarding session

Hello, i got a weird situation regarding IE6 and don’t know if the
problem is on Rails itself, on IE, or on our own Sharehosting but the
problem is like this :
There r user trying to login to our site and it’s successfull getting
into user private page but when the user click “something” link that
use AJAX call, suddenly it’s fair and nothing happen anymore the page
just static and neither of the links in the private page work…
but… the strange thing is suddenly all “user” just can’t login using
IE6 (but it works on FireFox), it just when the user submit the login
button it always redirect to home again although the login name and
password success and there is no error on rails log or any the page
just throw back to home everytime a user try to login… and it
happen about 1 hour approximate after that everything suddenly just
back to normal… I’m already got this problem twice and until now
still doesn’t have any clue bout what’s wrong…
Does anybody has the same issue as me ? I’m using Rails 2.2.2
Thanx