Creating an ACL for full group/user permissions

[Puc]

Hi,

I need to create a database structure (not built in ACL) for groups and user access to certain data. I have done this for just users, but need to get the database structure for a full users, groups, permissions implementation.

I know someone out these has a structure already defined. It needs to behave like Microsoft's user/groups setup.

Appreciate any help on this as its a load of tables to work out and i'm up against it, time wise.

Thanks.