diff --git a/gdk/gdkproperty.h b/gdk/gdkproperty.h
index 331191c487..afba2d2bfe 100644
--- a/gdk/gdkproperty.h
+++ b/gdk/gdkproperty.h
@@ -15,7 +15,7 @@ typedef enum
 } GdkPropMode;
 
 GdkAtom gdk_atom_intern	    (const gchar *atom_name,
-			     gint	  only_if_exists);
+			     gboolean	  only_if_exists);
 gchar*	gdk_atom_name	    (GdkAtom atom);
 gboolean gdk_property_get   (GdkWindow	 *window,
 			     GdkAtom	  property,
diff --git a/gdk/x11/gdkproperty-x11.c b/gdk/x11/gdkproperty-x11.c
index ee270b1e74..55197be742 100644
--- a/gdk/x11/gdkproperty-x11.c
+++ b/gdk/x11/gdkproperty-x11.c
@@ -34,7 +34,7 @@
 
 GdkAtom
 gdk_atom_intern (const gchar *atom_name,
-		 gint         only_if_exists)
+		 gboolean     only_if_exists)
 {
   GdkAtom retval;
   static GHashTable *atom_hash = NULL;