[Knoppix 3.7] dead ssh connection can not be killed

Hallo

I have a problem with an old ssh connection:

Sshd runs on knoppix 3.7. I connect it sometimes with PUTTY from WinXP Prof. SP2.

One time, I commanded “halt” trough putty, but I didn’t close actively the ssh-connection. Since then I have a dead ssh connection with an invalid PID. Reboot don't help.

Please see the following:

root@knopp:~# who -uT
root + pts/0 Nov 15 11:22 . 2456 (10.10.10.99)
root ? pts/8 Oct 22 16:09 ? 2494 (10.10.10.99)
root@knopp:~# kill -9 2494
-bash: kill: (2494) - Kein passender Prozess gefunden (no matching process found...)

How could I close the old connection on pts/8?

Thank You!

Regards,
rw