NRE stacktrace

gistfile1.txt

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object
  at MonoDevelop.MacDev.PlistEditor.CustomPropertiesWidget.FindOrAddPObject (TreeIter iter, System.String id, MonoDevelop.MacDev.PlistEditor.PObject item, System.Collections.Generic.Dictionary`2 tree) [0x000e9] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/CustomPropertiesWidget.cs:536 
  at MonoDevelop.MacDev.PlistEditor.CustomPropertiesWidget.AddToTree (Gtk.TreeStore treeStore, TreeIter iter, MonoDevelop.MacDev.PlistEditor.PObject current, System.Collections.Generic.Dictionary`2 tree) [0x00018] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/CustomPropertiesWidget.cs:495 
  at MonoDevelop.MacDev.PlistEditor.CustomPropertiesWidget.RefreshTree () [0x0002c] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/CustomPropertiesWidget.cs:580 
  at MonoDevelop.MacDev.PlistEditor.CustomPropertiesWidget.<SetPListContainer>m__2D (System.Object , System.EventArgs ) [0x00000] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/CustomPropertiesWidget.cs:84 
  at (wrapper delegate-invoke) <Module>:invoke_void__this___object_EventArgs (object,System.EventArgs)
  at (wrapper delegate-invoke) <Module>:invoke_void__this___object_EventArgs (object,System.EventArgs)
  at MonoDevelop.MacDev.PlistEditor.PObject.OnChanged (System.EventArgs e) [0x00019] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/PListObject.cs:243 
  at MonoDevelop.MacDev.PlistEditor.PObject.OnChanged (System.EventArgs e) [0x0002c] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/PListObject.cs:246 
  at MonoDevelop.MacDev.PlistEditor.PValueObject`1[System.String].set_Value (System.String value) [0x00007] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/PListObject.cs:294 
  at MonoDevelop.MacDev.PlistEditor.PDictionary.SetString (System.String key, System.String value) [0x0001e] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MacDev/MonoDevelop.MacDev/MonoDevelop.MacDev.PlistEditor/PListObject.cs:599 
  at MonoDevelop.MonoMac.PlistEditor.DocumentTypeWidget+<DocumentTypeWidget>c__AnonStorey9.<>m__2 (System.Object , System.EventArgs ) [0x0002d] in /Users/builder/data/lanes/monodevelop-lion-master/044fb884/source/md-addins/MonoDevelop.MonoMac/MonoDevelop.MonoMac/PlistEditor/DocumentTypeWidget.cs:81 
  at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x000d5] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System.Reflection/MonoMethod.cs:226 
  --- End of inner exception stack trace ---
  at System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x000eb] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System.Reflection/MonoMethod.cs:234 
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System.Reflection/MethodBase.cs:96 
  at System.Delegate.DynamicInvokeImpl (System.Object[] args) [0x000bf] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System/Delegate.cs:413 
  at System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) [0x00018] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System/MulticastDelegate.cs:70 
  at System.Delegate.DynamicInvoke (System.Object[] args) [0x00000] in /private/tmp/source/bockbuild/profiles/mono-2-10/build-root/mono-2.10.10/_build/mono-2.10.10.git/mcs/class/corlib/System/Delegate.cs:387 
  at GLib.Signal.ClosureInvokedCB (System.Object o, GLib.ClosureInvokedArgs args) [0x00000] in <filename unknown>:0 
  at GLib.SignalClosure.Invoke (GLib.ClosureInvokedArgs args) [0x00000] in <filename unknown>:0 
  at GLib.SignalClosure.MarshalCallback (IntPtr raw_closure, IntPtr return_val, UInt32 n_param_vals, IntPtr param_values, IntPtr invocation_hint, IntPtr marshal_data) [0x00000] in <filename unknown>:0