If set global variables as global in function,
first time works fine, but second wrong.
=======================
<?php
$hoge = 'hoge';
function a() {
  while (list($name,) = each( $GLOBALS )) {
    global $$name;
  }
  echo "hoge: $hoge<br>\n";
}
a();
a();
a();
?>
=======================
It displays
=======================
hoge: hoge
hoge:
hoge:
=======================