Plus d'application graphique en console

Bonjour,
j'ai un problème, je n'arrive plus à lancer de programme avec une interface graphique (comme kate, compiz ou tout autre application) via la console de mon debian.
exemple de message d'erreur :
debian:~# kate
kate: cannot connect to X server

debian:~# wicd-client
/var/lib/python-support/python2.5/gtk-2.0/gtk/__init__.py:72: GtkWarning: could not open display
warnings.warn(str(e), _gtk.Warning)
Loading...
Attempting to connect tray to daemon...
Success.
/usr/lib/wicd/wicd-client.py:333: Warning: invalid (NULL) pointer instance
self.menu = (self.manager.get_widget('/Menubar/Menu/About').
/usr/lib/wicd/wicd-client.py:333: Warning: g_signal_connect_data: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
self.menu = (self.manager.get_widget('/Menubar/Menu/About').
/usr/lib/wicd/wicd-client.py:333: GtkWarning: gtk_settings_get_for_screen: assertion `GDK_IS_SCREEN (screen)' failed
self.menu = (self.manager.get_widget('/Menubar/Menu/About').
/usr/lib/wicd/wicd-client.py:333: Warning: g_object_get: assertion `G_IS_OBJECT (object)' failed
self.menu = (self.manager.get_widget('/Menubar/Menu/About').
/usr/lib/wicd/wicd-client.py:333: Warning: value "TRUE" of type `gboolean' is invalid or out of range for property `visible' of type `gboolean'
self.menu = (self.manager.get_widget('/Menubar/Menu/About').
/usr/lib/wicd/wicd-client.py:445: Warning: invalid (NULL) pointer instance
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: Warning: g_signal_connect_data: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: Screen for GtkWindow not set; you must always set
a screen for a GtkWindow before using the window
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_screen_get_default_colormap: assertion `GDK_IS_SCREEN (screen)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_colormap_get_visual: assertion `GDK_IS_COLORMAP (colormap)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_screen_get_root_window: assertion `GDK_IS_SCREEN (screen)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_window_new: assertion `GDK_IS_WINDOW (parent)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_screen_get_display: assertion `GDK_IS_SCREEN (screen)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_display_sync: assertion `GDK_IS_DISPLAY (display)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_drawable_get_display: assertion `GDK_IS_DRAWABLE (drawable)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_x11_get_xatom_by_name_for_display: assertion `GDK_IS_DISPLAY (display)' failed
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: /build/buildd/gtk+2.0-2.12.11/gdk/x11/gdkdrawable-x11.c:878 drawable is not a pixmap or window
gtk.StatusIcon.__init__(self)
/usr/lib/wicd/wicd-client.py:445: GtkWarning: gdk_x11_display_get_xdisplay: assertion `GDK_IS_DISPLAY (display)' failed
gtk.StatusIcon.__init__(self)
Erreur de segmentation