title: Gtk# in monodevelop not working anymore after upgrading to ubuntu 11.10 unity
body: <p>I had some monodevelop programs with a GTK# user interface running smoothly in ubuntu 11.04 without unity. I have upgraded to ubuntu 11.10 with unity. Now I get the following error:</p>
  
  <blockquote>
    <p>"The type or namespace name 'Gtk' could not be found. Are you missing an assembly reference?".</p>
  </blockquote>
  
  <p>And indeed in my references the references atk-sharp, gdk-sharp, glade-sharp, glid-sharp, stk-sharp and pango-sharp are colored red and I can't re-add them.</p>
  
  <p>If I search in the software to install at gtk-sharp then it tells me Gtk# 2.10 is installed.
  If I start a new gtk project in monodevelop it gives the same errors.</p>