[Samba] file locking on Samba

[Arjen]

Hi,

many questions about locking have already been posted to the list, and 
since I could not find the answer to this one, allow me to pose mine.

Samba version samba-2.2.7a-8.9.0 as a RedHat package

All clients Windows 2k pro.

The office is an architect, who uses Bentley MicroStation SE. They write 
their design files over the network to the Samba server. When user A 
opens a file he can write to it. When user B opens the same file from 
another stations as user A is working on it, user B can also write to it.

Is there no way to lock the file for writing as soon as one user has 
opened it, so that others have only read access?


Thank you,
Arjen.