Skype doesn't start anymore

[lindelof]

This is what I get on the console when I start Skype:

$ skype
/usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Failed to load type module: /usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so

/usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Failed to load type module: /usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so

(<unknown>:7773): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/immodules/im-ibus.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Loading IM context type 'ibus' failed

(<unknown>:7773): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/immodules/im-ibus.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Loading IM context type 'ibus' failed
/usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Failed to load type module: /usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so

/usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Failed to load type module: /usr/lib/gtk-2.0/2.10.0/menuproxies/libappmenu.so

(<unknown>:7773): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/immodules/im-ibus.so: wrong ELF class: ELFCLASS64

(<unknown>:7773): Gtk-WARNING **: Loading IM context type 'ibus'

Skype used to work just fine before. I'm not 100% sure but the recent upgrade to Ubuntu 11.04 could coincide with the appearance of this bug.

Ubuntu version:

$ lsb_release -rd
Description: Ubuntu 11.04
Release: 11.04