Redirect problem with FF3

[Strangeplant]

I have a redirect problem in FF3, but not FF2. The error is seen as this:

The browser has stopped trying to retrieve the requested item. The
site is redirecting the request in a way that will never complete.

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In my first page, I'm starting a session, passing a variable to a second page and doing something, then going back to the first page (or elsewhere). The first page is redirecting to the second with:

    header("Location: /prd/firsttsk.php");

and the second page redirecting with:

	header("Location: /prd/" . $_SESSION['page'] . "/index.php");

The document root structure, in Linux Apache is /var/www/html, so the base from the URL is /html. I've tried other paths, but I either get session reset because the URL's are different, or other path problems, and haven't found a combination that works with FF3. I must be doing something wrong, although a search on the web uncovers may other users having redirect problems with FF3. How should I change my code so it works with all browsers?

[Jesdisciple]

Are both of those redirects unconditional? Better yet, can we see all relevant parts (or all) of the PHP?