Locking a whole Database on Server

[Stan Busk]

Hi,

Is it possible to lock access to a whole database from Embedded  
Server? I just want to allow first client to connect, if some  
maintenance has to be performed lock access to all other clients  
until the maintenance is done. I have seen that a lot of time in 4D.  
I just need to be able to send a given error to all the other clients  
trying to connect so they can wait until the lock is released. I can  
then display a 'Maintenance on the way, please wait' dialog. Is it  
possible with Valentina Embedded Server?

Stan