diff --git a/gst-libs/gst/rtp/gstbasertppayload.c b/gst-libs/gst/rtp/gstbasertppayload.c
index 783e40205a..c7746d5cd4 100644
--- a/gst-libs/gst/rtp/gstbasertppayload.c
+++ b/gst-libs/gst/rtp/gstbasertppayload.c
@@ -453,7 +453,8 @@ no_function:
  */
 void
 gst_basertppayload_set_options (GstBaseRTPPayload * payload,
-    gchar * media, gboolean dynamic, gchar * encoding_name, guint32 clock_rate)
+    const gchar * media, gboolean dynamic, const gchar * encoding_name,
+    guint32 clock_rate)
 {
   g_return_if_fail (payload != NULL);
   g_return_if_fail (clock_rate != 0);
@@ -504,8 +505,8 @@ update_max_ptime (GstBaseRTPPayload * basertppayload)
  * Returns: %TRUE if the caps could be set.
  */
 gboolean
-gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload, gchar * fieldname,
-    ...)
+gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload,
+    const gchar * fieldname, ...)
 {
   GstCaps *srccaps, *peercaps;
   gboolean res;
diff --git a/gst-libs/gst/rtp/gstbasertppayload.h b/gst-libs/gst/rtp/gstbasertppayload.h
index 4802ae88d8..afdbffc59f 100644
--- a/gst-libs/gst/rtp/gstbasertppayload.h
+++ b/gst-libs/gst/rtp/gstbasertppayload.h
@@ -139,12 +139,13 @@ struct _GstBaseRTPPayloadClass
 GType           gst_basertppayload_get_type             (void);
 
 void            gst_basertppayload_set_options          (GstBaseRTPPayload *payload,
-                                                         gchar *media, gboolean dynamic,
-                                                         gchar *encoding_name,
+                                                         const gchar *media,
+                                                         gboolean dynamic,
+                                                         const gchar *encoding_name,
                                                          guint32 clock_rate);
 
 gboolean        gst_basertppayload_set_outcaps          (GstBaseRTPPayload *payload,
-                                                         gchar *fieldname, ...);
+                                                         const gchar *fieldname, ...);
 
 gboolean        gst_basertppayload_is_filled            (GstBaseRTPPayload *payload,
                                                          guint size, GstClockTime duration);