How to modify the username of WIN2003 Administrator with Group Policy _ Application Tips

Because my client is XP username is administrator my win2003 server to enable shared files, so that my win2003 server to use the account administrator password is empty, clients can browse my shared resources, in order to secure the meantime, I would like to Administrator this username should be the right or rename, there are know brother say

To modify the method:
I know. To open Group Policy, select Computer Configuration →windows settings → security settings → Local policies → security options, and in the right pane, double-click the account: Rename system Administrator account item

Group Policy Entry method: Running-gpedit.msc