nautilus opening error 26_2_2012

lhk@ubuntu:~$ nautilus
Gtk-Message: Failed to load module "canberra-gtk-module"
Gtk-Message: Failed to load module "canberra-gtk-module"
** (nautilus:3840): DEBUG: SyncDaemon already running, initializing SyncdaemonDaemon object
Initializing nautilus-open-terminal extension
Initializing nautilus-gdu extension
nautilus: symbol lookup error: nautilus: undefined symbol: ubuntu_menu_proxy_get