fatal error in browser

[cruz]

I get a fatol error message in my browser on the homepage of one of my sites. My other sites are working just fine. Here is the message.
Fatal error: session_start() [<a href='function.session-start'>function.session-start</a>]: Failed to initialize storage module: user (path: /var/lib/php5) in /var/www/web1/web/init.php on line 3
Here is the beginning lines if init.php <?php

session_start();
error_reporting( E_ERROR );

define ('FULL_PATH', dirname(__FILE__).'/');

if (!is_readable(FULL_PATH.'myconfigs/config.php') ) {
if (is_readable('install.php')){
header("location: install.php");
} else {
header("location: ../install.php");
}
}
There is nothing in /var/lib/php5.

[falko]

What's the output of ls -la /var/lib/php5?

[cruz]

drwx-wx-wt 2 root root 4096 2008-04-05 11:09 .
drwxr-xr-x 30 root root 4096 2008-02-01 15:28 ..

[topdog]

what are you using for session management ?