At 01.19 15/06/2003 +1000, you wrote:

>Well, my prejudices tell me that one filesystem's system can't set
>attributes on another system's filesystem. So fbserver on host A can't
>open database file on host B with exclusive access...

I am not speaking about "setting attributes"
my experience on SMB tells me that if I open from a client a file on a
Server with
"Deny Write" sharing attribute
noone from the network or the server will be able to open the file.
In SMB the redirector on the client is in sync with the one on the server,
so when a file is opened by a client with deny write the server will reject
the request
from other clients.
Regards
Marco