Session Cookie Not Ending In IE

Cookie name is "viewStatus" value saved is 1

Closing all windows should end the session but on the reopening cookie page I find the session cookie is still alive.

If I alert(document.cookie) I get viewStatus = 1

If I rename the cookie to say "vStatus" and close the window when I reopen it and alert(document.cookie) I get

viewstatus=1 vStatus=1

any ideas?

This only happens in IE ( as always)

PS

I just did a little experiment, I closed all windows, created a new file with just

<script>
alert(document.cookie)
</script>

in it then opened the file and still got

viewstatus=1 vStatus=1

I know I did not have this problem before because I have a session cookie example on my site and that does not work now so is it something new that is wrong with IE.