$_SESSION lost

Hi, I've just installed PHP 5.2.4 on a FC 7 with a web server. $ php -v PHP 5.2.4 (cli) (built: Sep 18 2007 08:50:58) Copyright (c) 1997-2007 The PHP Group Zend Engine v2.2.0, Copyright (c) 1998-2007 Zend Technologies It seems some PHP module might be missing, I tested it with a page1.php: session_start(); $_SESSION['favcolor'] = 'green'; Then I click a link in page1.php to go another page2.php: session_start(); echo "favcolr =" . $_SESSION['favcolor']; It only displayed "favcolr =", it was empty in $_SESSION['favcolor']. The test script page1.php and page2.php are working fine on other machines. I checked with php modules, the "session" is there. What could I be missing in PHP modules or setup? Thank you.