diff --git a/dom/public/range/nsIDOMSelection.h b/dom/public/range/nsIDOMSelection.h
index b52b9b022f88..7e3ccc003deb 100644
--- a/dom/public/range/nsIDOMSelection.h
+++ b/dom/public/range/nsIDOMSelection.h
@@ -32,6 +32,15 @@ class nsIDOMRange;
  { 0xa6cf90e1, 0x15b3, 0x11d2, \
   { 0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32 } } 
 
+#ifndef SELECTIONTYPE
+enum SelectionType{SELECTION_NORMAL = 0, 
+                   SELECTION_SPELLCHECK, 
+                   SELECTION_IME_SOLID, 
+                   SELECTION_IME_DASHED, 
+                   NUM_SELECTIONTYPES};
+#define SELECTIONTYPE
+#endif
+
 class nsIDOMSelection : public nsISupports {
 public:
   static const nsIID& GetIID() { static nsIID iid = NS_IDOMSELECTION_IID; return iid; }