[Samba] howto kill connection to an smbclient

[André Weidemann]

I read through the man pages and could not find anything but swat to 
kill a connection to a samba client.
I have the following situation.
I have a CD-changer with 6 discs that serves a video archive.
Upon magazine insertion I start mounting all 6 discs in row.
To be able to eject the magazine again I have to umount each disc.
Unfortunatly I get a device busy on the last disc that was accessed.
I tried "smbcontrol smbd close-share (sharename/busy drive)" but that 
did not do it.
I can only restart samba (which is not my intention) or I can use swat, 
click on status and kill the connection to the client. But this is not 
doable for my kind of configutration since I have to umount the drives 
through a script.
Any suggestions on how I can kill the connection to the client on the 
command line are greatly appreciated.

  André.