Description:
------------
Previously I submitted a bug report about sessions not working, in the sense that every session_start() call created a new session, and a new file in /tmp. I have concluded that the host name "spare_ribs" was the issue. By changing the hostname to "spareribs" (no '_') the session issue is fixed. I am not sure if using '_' in a hostname is against some RFC and thus this is not really a bug, but I think that since bind accepted it, and the two browsers I tried with it worked fine, this is not breaking protocol and should work fine.

(Apache 2.0.52 being used here.)

Reproduce code:
---------------
Set hostname to anything with _ such as "spare_ribs". Then reboot box and browse to page one which includes the following code.

/* Page 1 */

<?php
 session_start();
 $_SESSION['test'] = 'this is a test.';

 echo $_SESSION['test'];
 echo '<a href="page2.php">click here for page 2</a>';

?>

/* Page 2 */

<?php
 session_start();
 echo 'You should see this is a test:';
 echo $_SESSION['test'];
 echo '<a href="page1.php">click here for page 1</a>';

?>



Expected result:
----------------
Page one should say 'this is a test', and page two should say 'You should see this is a test: this is a test'. 

Actual result:
--------------
However page two only says 'You should see this is a test'. And a new session id has been assigned, as well as a new session created in /tmp.