Enabling CCK Permissions does not allow changes

to allowed valued list.
Hi i've enabled the cck permissions module-option in order to use it . After enabling the module i tried to edit the allowed values list by changing for example the 'option Alpha' to 'option Alpha Subalpha' but although it seems like it's and it updates ok after trying to create a new node the old data is stored!so nothing changes i tried to 'rebuild permissions' from the post settings option inside the admin panel but still nothing ?
does anyone knows why ?
thanx!!!
p.s : please note that i tried to go manually and change it from phpmyadmin inside the table but it's not possible :)