[php] problema variabili globali

[ateicos]

file core_exec.php

$cippa = "lippa";
    include( "core_user.php" );
    include( "core_page.php" );
    include( "core_menu.php" );
    include( "core_functions.php" );
echo "[";
    user_check();
echo "]"; 

file core_user.php

function user_check() {
    global $function_count; $function_count++;
    global $_PAGE;
    global $_USER;

    global $cippa ;
echo $cippa;
...
} 

viene fuori [], senza nulla all'interno...

cosa sbaglio?