Ubuntu – ny way to kill a zombie process without reboot

Is there any way to kill a zombie process without reboot? Here is how it happened:

I want to download a 12GB file using torrent. After adding the .torrent file, transmission turned into a zombie process (I tried ktorrent too. Same behavior). Finally I could download the file using µTorrent but after closing the program, it turns into a zombie as well.

I tried using kill, skill and pkill with different options and -9 signal but no success.

After reading some solutions on web, I found out killing the parent can kill the zombie. But killing wine didn't help either.

Is there another way?

Edit:

ps -o pid,ppid,stat,comm

PID  PPID STAT COMMAND
7121  2692 Ss   bash
7317  7121 R+   ps

pstree output:

init─┬─GoogleTalkPlugi───4*[{GoogleTalkPlug}]
 ├─NetworkManager─┬─dhclient
 │                └─{NetworkManager}
 ├─acpid
 ├─amarok───19*[{amarok}]
 ├─apache2───5*[apache2]
 ├─atd
 ├─avahi-daemon───avahi-daemon
 ├─bonobo-activati───{bonobo-activat}
 ├─clock-applet
 ├─console-kit-dae───63*[{console-kit-da}]
 ├─cron
 ├─cupsd
 ├─2*[dbus-daemon]
 ├─2*[dbus-launch]
 ├─desktopcouch-se───desktopcouch-se
 ├─firefox───run-mozilla.sh───firefox-bin─┬─plugin-containe───8*[{plugin-contain}]
 │                                        └─14*[{firefox-bin}]
 ├─gconfd-2
 ├─gdm-binary─┬─gdm-simple-slav─┬─Xorg
 │            │                 ├─gdm-session-wor─┬─gnome-session─┬─bluetooth-apple
 │            │                 │                 │               ├─compiz───sh───gtk-window-deco
 │            │                 │                 │               ├─fusion-icon
 │            │                 │                 │               ├─gdu-notificatio
 │            │                 │                 │               ├─gnome-panel───{gnome-panel}
 │            │                 │                 │               ├─gnome-power-man
 │            │                 │                 │               ├─gpg-agent
 │            │                 │                 │               ├─gwibber-service
 │            │                 │                 │               ├─nautilus
 │            │                 │                 │               ├─nm-applet
 │            │                 │                 │               ├─polkit-gnome-au
 │            │                 │                 │               ├─2*[python]
 │            │                 │                 │               ├─qstardict───{qstardict}
 │            │                 │                 │               ├─ssh-agent
 │            │                 │                 │               ├─tracker-applet
 │            │                 │                 │               ├─trackerd
 │            │                 │                 │               ├─wakoopa─┬─wakoopa
 │            │                 │                 │               │         └─3*[{wakoopa}]
 │            │                 │                 │               └─{gnome-session}
 │            │                 │                 └─{gdm-session-wo}
 │            │                 └─{gdm-simple-sla}
 │            └─{gdm-binary}
 ├─6*[getty]
 ├─gnome-keyring-d───2*[{gnome-keyring-}]
 ├─gnome-screensav
 ├─gnome-settings-
 ├─gnome-system-mo
 ├─gnome-terminal─┬─bash───ssh
 │                ├─bash───pstree
 │                ├─gnome-pty-helpe
 │                └─{gnome-terminal}
 ├─gvfs-afc-volume───{gvfs-afc-volum}
 ├─gvfs-fuse-daemo───3*[{gvfs-fuse-daem}]
 ├─gvfs-gdu-volume
 ├─gvfsd
 ├─gvfsd-burn
 ├─gvfsd-computer
 ├─gvfsd-metadata
 ├─gvfsd-trash
 ├─hald─┬─hald-runner─┬─hald-addon-acpi
 │      │             ├─hald-addon-cpuf
 │      │             ├─hald-addon-inpu
 │      │             └─hald-addon-stor
 │      └─{hald}
 ├─indicator-apple
 ├─indicator-me-se
 ├─indicator-sessi
 ├─irqbalance
 ├─kded4
 ├─kdeinit4─┬─kio_http_cache_
 │          └─klauncher
 ├─kglobalaccel
 ├─modem-manager
 ├─multiload-apple
 ├─mysqld───10*[{mysqld}]
 ├─named───10*[{named}]
 ├─nmbd
 ├─notification-ar
 ├─notify-osd
 ├─polkitd
 ├─pulseaudio─┬─gconf-helper
 │            └─2*[{pulseaudio}]
 ├─rsyslogd───2*[{rsyslogd}]
 ├─rtkit-daemon───2*[{rtkit-daemon}]
 ├─smbd───smbd
 ├─snmpd
 ├─sshd
 ├─timidity
 ├─trashapplet
 ├─udevd───2*[udevd]
 ├─udisks-daemon─┬─udisks-daemon
 │               └─{udisks-daemon}
 ├─upowerd
 ├─upstart-udev-br
 ├─utorrent.exe───{utorrent.exe}
 ├─vnstatd
 ├─winbindd───2*[winbindd]
 ├─wnck-applet
 ├─wpa_supplicant
 └─xinetd

System monitor and top show the zombie process is using resources:

Edit 2:
I think I found something. I tried to logout and saw this message:

Since other torrent clients have th same issue maybe it's something about file size.I'm using ubuntu 10.04 on ext4 partitions.Killing nautilus and sending SIGCHLD signal to it didn't work.