Too many defunct processes; kill -9 not working

[Eitan Adler]

Lately I've been getting a considerable number of defunct processes. I
do not know of any major event that changed my computer (ie it is not
related to an ports update or a freeBSD upgrade).

This is often caused by me killing the process using kill -15 or kill
-3 or kill -9.

What can I do to determine why processes are not getting killed by kill -9?

% ps -o ppid -o comm|grep defunct|cut -d ' ' -f 1 |xargs kill -9
typically gets rid of them (by killing their parent)

-- 
Eitan Adler