Here we go:

1) You need to create the schema owner. In Unix this is normally baan and in NT often baandb:

create user baan identified by xyz;
grant ressource to baan;
grant connect to baan;

2) You need to create the role which all Baan users belong to. In Unix, this is r_baan:

create role r_baan;

3) You need to create the actual Oracle users for the Baan users, see ora_users file:

create user heinz identified by XYZ;
grant connect to heinz;
grant ressource to heinz;
grant r_baan to heinz;

(Original text by Markus Schmitz)