Unkillable zombie sshd-s?

[Ivan Voras]

Mark Andrews wrote:
>>Is there a way to find out what has happened and why does the situation 
>>occur? (I can't reboot the server for testing)
> 
> 	You can't kill them because they are already dead.  They
> 	are just holding state so that the parent process can know
> 	how they died.  Once the parent process wait()'s on them
> 	(or the parent dies) they will disappear.

I knew that (except the bit that they're ukillable by design :) ), but I 
was hoping it's a known ssh problem - this is the first time I saw sshd 
processes as zombies (and it seems they've been zombies for a long time, 
so parents are probably in error).

Can I find out what their parent processes are? (something like 
tree-shaped ps?)