Bug : always this last line in message list

[Emmanuel <e allaud wanadoo fr>]

	Hi all,
if you have a collapsed thread near the last message, and you've selected 
a message in the message list (before the thread), you expand the 
collapsed thread then you scroll to the last lise (which has disappeared) 
and you'll see that the last line is the selected message!! But if you 
click on it, it displays correctly the last message (and correctly 
refreshes the last line also).
Argh, we should really fix this damn last line unbehaves! :)
Bye
Manu