Thanks for your quick response, I just tested your answer and you're right it does. What a nightmare, if someone reloads the page the check will fail. But now I know what it is happening I can store it as a session variable.
It's very strange, I was having the exact same problem, because the requested file was a perl script I was able to log each attempt. And the results were very interesting....
Firefox shows the correct HTTP_ACCEPT value because it was making a SINGLE request on my perl script. Now, for a reason that still I don't understand IE is making TWO requests on the same file, first logged requests shows a full HTTP_ACCEPT field with values, second logged requests shows a */*.
Why is IE making two requests on the same file?
I tried doing GET's directly from a Unix commmand prompt, then with Firebox and they all behave correctly! only IE hits the script twice for no reason! is this a IE bug?