Giver crash after run

Binary package hint: giver

I'm running giver from terminal, program crash and print this messages:

[Debug]: PhotoService static constructor called
[Debug]: New GiverService was created
[Debug]: We have the port : 40852
[Debug]: About to create the Avahi client
[Debug]: Adding Avahi Service _giver._tcp
[Debug]: Avahi Service _giver._tcp is added
[Debug]: GiverService:OnEntryGroupStateChanged was called state: Registering
[Debug]: About to call ServiceAdded
[Debug]: ServiceAdded was just called
Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
System.DllNotFoundException: libX11.so
  at (wrapper managed-to-native) Egg.TrayIcon:XInternAtom (intptr,string,bool)
  at Egg.TrayIcon.OnRealized () [0x00000] in <filename unknown>:0
  at Gtk.Widget.realized_cb (IntPtr widget) [0x00000] in <filename unknown>:0
   at GLib.ExceptionManager.RaiseUnhandledException(System.Exception e, Boolean is_terminal)
   at Gtk.Widget.realized_cb(IntPtr widget)
   at Gtk.Widget.gtk_widget_show_all(IntPtr )
   at Gtk.Widget.ShowAll()
   at Giver.Application.SetupTrayIcon()
   at Giver.Application.InitializeIdle()
   at GLib.Idle+IdleProxy.Handler()
   at Gtk.Application.gtk_main()
   at Gtk.Application.Run()
   at Gnome.Program.Run()
   at Giver.Application.StartMainLoop()
   at Giver.Application.Main(System.String[] args)

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: giver 0.1.8-6
ProcVersionSignature: Ubuntu 2.6.38-9.43-generic 2.6.38.4
Uname: Linux 2.6.38-9-generic i686
Architecture: i386
Date: Thu May 19 20:20:12 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
PackageArchitecture: all
ProcEnviron:
 SHELL=/bin/bash
 LC_NUMERIC=C
 LANG=pl_PL.utf8
 LANGUAGE=pl_PL:en
SourcePackage: giver
UpgradeStatus: No upgrade log present (probably fresh install)