Authorization Script - Please Help!

[POGRAN]

I am writing authorization script for my website..
almost everything is done, except one thing:
after visitor logs in, he gets message about successfull authorization, everything is ok, BUT
when he wants to navigate to another page he gets back the form of Authorization!
I don't undersrand why the session is finished after the visitor goes to another page,

My example script contains 3 pages:
auth.inc - file that contains functions!
login.php - regular website page, that requires authorization..
another.php - copy of login.php, needed to see that session is no longer available after visitor changes page..

I didn't want to make this topic to big an not-understanable, so I uploaded source code of my 3 pages, here you can see them:
[a href=\"http://pogran.nm.ru/auth.inc.html\" target=\"_blank\"]http://pogran.nm.ru/auth.inc.html[/a]
[a href=\"http://pogran.nm.ru/login.html\" target=\"_blank\"]http://pogran.nm.ru/login.html[/a]
[a href=\"http://pogran.nm.ru/another.html\" target=\"_blank\"]http://pogran.nm.ru/another.html[/a]

I hope that somebody would spare some 2-3 minutes to look at my script files and say me the reason or maybe would give me some analogue workable script.
Thanks in advance..

[redarrow]

<? session_start();
?>

session_start();

You must keep the seesion_start at the top of all pages ok.

[POGRAN]

no, unfortunely it didn't help :(
still gets back to authorization form..

[POGRAN]

what nobody can help? :(
i don't believe it..