diff --git a/gst/gobject2gtk.h b/gst/gobject2gtk.h
index 9a4ac4160e..34e4d8313e 100644
--- a/gst/gobject2gtk.h
+++ b/gst/gobject2gtk.h
@@ -100,18 +100,18 @@ struct _GTypeInfo
   /* interface types, classed types, instantiated types */
   guint16                class_size;
 
-  gpointer               base_init;
+  GBaseInitFunc          base_init;
   gpointer               base_finalize;
 
   /* classed types, instantiated types */
-  gpointer               class_init;
+  GClassInitFunc         class_init;
   gpointer               class_finalize;
   gconstpointer          class_data;
   
   /* instantiated types */
   guint16                instance_size;
   guint16                n_preallocs;
-  gpointer               instance_init;
+  GInstanceInitFunc      instance_init;
 
   /* value handling */
   const gpointer         value_table;
diff --git a/gst/gstinfo.c b/gst/gstinfo.c
index c3dfffd7a3..25a0928b35 100644
--- a/gst/gstinfo.c
+++ b/gst/gstinfo.c
@@ -142,9 +142,10 @@ guint32 _gst_debug_categories = 0x00000000;
  *   DEBUG(pid:cid):gst_function:542(args): [elementname] something neat happened
  */
 void
-gst_default_debug_handler (gint category, gboolean incore, gchar *file, gchar *function,
-                            gint line, gchar *debug_string,
-                            void *element, gchar *string)
+gst_default_debug_handler (gint category, gboolean incore,
+			   const gchar *file, const gchar *function,
+			   gint line, const gchar *debug_string,
+			   void *element, gchar *string)
 {
   gchar *empty = "";
   gchar *elementname = empty,*location = empty;
@@ -257,9 +258,10 @@ guint32 _gst_info_categories = 0x00000001;
  *   INFO:gst_function:542(args): [elementname] something neat happened
  */
 void
-gst_default_info_handler (gint category, gboolean incore,gchar *file, gchar *function,
-                           gint line, gchar *debug_string,
-                           void *element, gchar *string)
+gst_default_info_handler (gint category, gboolean incore,
+			  const gchar *file, const gchar *function,
+			  gint line, const gchar *debug_string,
+			  void *element, gchar *string)
 {
   gchar *empty = "";
   gchar *elementname = empty,*location = empty;
diff --git a/gst/gstinfo.h b/gst/gstinfo.h
index 71fdba9f4c..113657c17a 100644
--- a/gst/gstinfo.h
+++ b/gst/gstinfo.h
@@ -116,12 +116,14 @@ extern const gchar *_gst_category_colors[32];
 //#endif
 
 
-typedef void (*GstDebugHandler) (gint category,gboolean core,gchar *file,gchar *function,
-                                 gint line,gchar *debug_string,
+typedef void (*GstDebugHandler) (gint category,gboolean core,
+				 const gchar *file,const gchar *function,
+                                 gint line,const gchar *debug_string,
                                  void *element,gchar *string);
 
-void gst_default_debug_handler (gint category,gboolean incore,gchar *file,gchar *function,
-                                gint line,gchar *debug_string,
+void gst_default_debug_handler (gint category,gboolean incore,
+				const gchar *file, const gchar *function,
+                                gint line,const gchar *debug_string,
                                 void *element,gchar *string);
 
 extern guint32 _gst_debug_categories;
@@ -233,12 +235,14 @@ G_GNUC_UNUSED static GModule *_debug_self_module = NULL;
  * INFO system
  **********************************************************************/
 
-typedef void (*GstInfoHandler) (gint category,gboolean incore,gchar *file,gchar *function,
-                                gint line,gchar *debug_string,
+typedef void (*GstInfoHandler) (gint category,gboolean incore,
+				const gchar *file,const gchar *function,
+                                gint line,const gchar *debug_string,
                                 void *element,gchar *string);
 
-void gst_default_info_handler (gint category,gboolean incore,gchar *file,gchar *function,
-                               gint line,gchar *debug_string,
+void gst_default_info_handler (gint category,gboolean incore,
+			       const gchar *file,const gchar *function,
+                               gint line,const gchar *debug_string,
                                void *element,gchar *string);
 
 extern GstInfoHandler _gst_info_handler;