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

I wanted to download a 12GB 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.

In some answers in 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
 +-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
 +-explorer.exe
 +-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
 ¦            ¦                 ¦                 ¦               +-fusion-icon---compiz---sh---gtk-window-deco
 ¦            ¦                 ¦                 ¦               +-gdu-notificatio
 ¦            ¦                 ¦                 ¦               +-gnome-panel
 ¦            ¦                 ¦                 ¦               +-gnome-power-man
 ¦            ¦                 ¦                 ¦               +-gpg-agent
 ¦            ¦                 ¦                 ¦               +-nautilus---bash
 ¦            ¦                 ¦                 ¦               ¦          +-{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-system-m}
 +-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-http
 +-gvfsd-metadata
 +-gvfsd-trash
 +-hald---hald-runner---hald-addon-acpi
 ¦      ¦             +-hald-addon-cpuf
 ¦      ¦             +-hald-addon-inpu
 ¦      ¦             +-hald-addon-stor
 ¦      +-{hald}
 +-hotot---xdg-open
 ¦       +-3*[{hotot}]
 +-indicator-apple
 +-indicator-me-se
 +-indicator-sessi
 +-irqbalance
 +-kded4
 +-kdeinit4---kio_http_cache_
 ¦          +-klauncher
 +-kglobalaccel
 +-knotify4
 +-modem-manager
 +-multiload-apple
 +-mysqld---10*[{mysqld}]
 +-named---10*[{named}]
 +-nmbd
 +-notification-ar
 +-notify-osd
 +-pidgin---{pidgin}
 +-polkitd
 +-pulseaudio---gconf-helper
 ¦            +-2*[{pulseaudio}]
 +-rsyslogd---2*[{rsyslogd}]
 +-rtkit-daemon---2*[{rtkit-daemon}]
 +-services.exe---plugplay.exe---2*[{plugplay.exe}]
 ¦              +-winedevice.exe---3*[{winedevice.exe}]
 ¦              +-3*[{services.exe}]
 +-smbd---smbd
 +-snmpd
 +-sshd
 +-timidity
 +-trashapplet
 +-udevd---2*[udevd]
 +-udisks-daemon---udisks-daemon
 ¦               +-{udisks-daemon}
 +-upowerd
 +-upstart-udev-br
 +-utorrent.exe---8*[winemenubuilder]
 ¦              +-{utorrent.exe}
 +-vnstatd
 +-winbindd---2*[winbindd]
 +-2*[winemenubuilder]
 +-wineserver
 +-wnck-applet
 +-wpa_supplicant
 +-xinetd

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