KMAIL, reorginizing messages

[Mike McMullin]

  I totally prefer Evolution over KMAIL, but unfortunately one particular list 
I'm on sees my normal addy as a spam source, so I have to use this secondary 
address and a separate mail client (KMAIL  :( )
  As I'm going through the list deleting messages individually and by thread 
<CTR-DEL>, kmail re-organizes the unread mail, often kicking me to the last 
bunch of messages, is there a way to turn off this obnoxious behaviour?