[Samba] How to send a domain wide message with smbclient?

[Travis L. Bean]

Is there a way to send a message to all users currently logged into a 
Samba domain controller?  The reason why I ask is that I have a Samba 
3.x.x primary/backup domain controller setup and as soon as the system 
monitor detects that the primary domain controller is offline I would 
like to execute a command to send a domain wide message telling all 
domain users to save their work to the local machine, log off the pdc 
and log back in to the bdc.  Is there a way to accomplish this with 
smbclient or another open source software solution?

Thanks,

Travis L. Bean
Systems Administrator
Bio-Logic Aqua Technologies
Grants Pass, OR - United States