Why don't processes kill when disconnected (AIX3.1.3003)?

[Tim Fredrick]

I hope this is something simple.  But when a terminal sessions is terminated
abnormally (power down, telnet disconnect, etc.) many processes stay in
the process tables.  This is also true when you press CTRL-SHIFT-BACKSPACE
in AIXWindows -- some X processes will stay in the process table as seen
by "ps -efgaux".

Some processes (like the game nethack) really need to get a "kill -HUP"
signal during these conditions so they can do error recovery.  Has anyone
else experienced this?  Is this a bug or a procedural problem?  Any insight
would be tremendously appreciated.  Thanks.  --Tim