Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
You are 100% right. The solution to my problem was within linux user UID/GID. As a matter of a fact there is some additional information on the page: http://www.redhat.com/docs/manuals/linux/RHL-9-Manual/admin-primer/s1-acctsgrps-rhlspec.html where it says: "UIDs and GIDs must be globally unique within your organization if you intend to share files and resources over a network. Otherwise, whatever access controls you put in place will fail to work properly, as they are based on UIDs and GIDs, not usernames and group names. Specifically, if the /etc/passwd and /etc/group files on a file server and a user's workstation differ in the UIDs or GIDs they contain, improper application of permissions can lead to security issues. For example, if user juan has a UID of 500 on a desktop computer, files juan creates on a file server will be created with owner UID 500. However, if user bob logs in locally to the file server (or even some other computer), and bob's account also has a UID of 500, bob will have full access to juan's files, and vice versa. Therefore, UID and GID collisions are to be avoided at all costs."