Sessions not working

Basic Info first. I am running Windows ME (don't know why just am) and I have downloaded PHPDEV423 and have also upgraded to PHP 4.3.0.

Everything on my computer seems to be working fine except sessions. I have tried a number of things and have tracked it down to sessions.

I have downloaded a couple of scripts from the web I suspect are a little old. These scripts logo a user in but they do not seem to work because of the sessions.

I have copied a test script out of a book I have and it does not work either, it looks like this:
<?
session_start();
session_register("your_name");
if(!empty($your_name))
{
echo "I already know you name, $your_name";
}
elseif(empty($your_name) && !isset($submit))
{
echo "<form name=myform method=post action=$PHP_SELF>
<input type=text name=first_name> first name<br>
<input type=test name=last_name> last name<br>
<input type=submit name=submit value=submit>
</form>";
} elseif (isset($submit) && empty($your_name))
{
$your_name = $first_name . " " . $last_name;
echo "Thank you, $your_name";
}
?>

On the first visit it should ask for your name and after hitting refresh if should say it already knows you name.

It does creat a session but the only thing it puts in the file is this:
!your_name|

I have tried globals on and off.

Has there been a change in the way sessions are handled that is making these scripts in need of a re-wright?

I have put many houre into trying to solve this problem and help would be greatly apperaciated.

you need to move session_register("your_name");

also look at http://www.php.net/docs.php
for $_SESSION & $_POST reguardless of register_global setting

Thank you for the reply I am starting to figure this out but the above code did not work for me either. I did however go through the sessions turtorial and that worked. What I would really like to know is why do none of the old scripts work there must be a way of configuring php to work with these old scripts. I got the script I posted out of MySQL/PHP Database Applications by Jay Breenspan and Brad Bulger and if it does not work then I need to know why so I will know if this is an old book that I need to trash or what, I just got it though so what is up?