[CRASH]

[Emmanuel <e allaud wanadoo fr>]

	Hi all,
here is a crash that is easily reproducible : open a window by 
double-clicking a message in an index. Then close the mailbox (by the 
mailbox context menu), then go back to the window with the message (this 
is not destroyed, that's the problem) then just click on the reply button 
for example--->crash!!
I think we should connect the destroy signals to the "close-mailbox" 
signal to be sure all related windows disappear when we close the mailbox 
to insure consistency.
Bye
Manu