how do you kill a zombie?

[Markus]

You can try with ps -Af or ps -auxf and look for the PPID to kill the parent process with kill -9 PID, kill -HUP PID or kill -SIGHUP PID. If this is kdeinit or somesuch you obviously have to restart it. Don't know if you can just kill the zombie as it's already terminated. AFAIK the only way is to kill the parentprocess.