PHP 5 supports static class variables.

<?php
class Globals {
    static 
$NAME "sterling";
    static 
$HOST "localhost";
    static 
$USER "sterling";
    static 
$PASS "itsasecret";
}

echo 
Globals::$NAME;
echo 
"\n<br />\n";
Globals::$HOST "db42.pair.com";
echo 
Globals::$HOST;
echo 
"\n<br />\n";
?>
Output
sterling
db42.pair.com