diff --git a/samples/richedit/wxlwindow.cpp b/samples/richedit/wxlwindow.cpp
index e767192d5c..f25d30b5fb 100644
--- a/samples/richedit/wxlwindow.cpp
+++ b/samples/richedit/wxlwindow.cpp
@@ -289,10 +289,13 @@ wxLayoutWindow::OnMouse(int eventId, wxMouseEvent& event)
          // selecting?
          if ( event.LeftIsDown() )
          {
-            wxASSERT_MSG( m_Selecting, "should be set in OnMouseLeftDown" );
-
-            m_llist->ContinueSelection(cursorPos, m_ClickPosition);
-            DoPaint();  // TODO: we don't have to redraw everything!
+            // m_Selecting might not be set if the button got pressed
+            // outside this window, so check for it:
+            if(m_Selecting)
+            {
+               m_llist->ContinueSelection(cursorPos, m_ClickPosition);
+               DoPaint();  // TODO: we don't have to redraw everything!
+            }
          }
 
          if ( u )