diff --git a/coreapi/linphonecore.c b/coreapi/linphonecore.c
index 3398bf822..a13e3921d 100644
--- a/coreapi/linphonecore.c
+++ b/coreapi/linphonecore.c
@@ -559,6 +559,8 @@ static void sip_config_read(LinphoneCore *lc)
 			break;
 		}
 	}
+	/*this is to filter out unsupported encryption schemes*/
+	linphone_core_set_media_encryption(lc,linphone_core_get_media_encryption(lc));
 
 	/*for tuning or test*/
 	lc->sip_conf.sdp_200_ack=lp_config_get_int(lc->config,"sip","sdp_200_ack",0);
@@ -4436,13 +4438,24 @@ bool_t linphone_core_media_encryption_supported(const LinphoneCore *lc, Linphone
 	return FALSE;
 }
 
-void linphone_core_set_media_encryption(LinphoneCore *lc, enum LinphoneMediaEncryption menc) {
-	if (menc == LinphoneMediaEncryptionSRTP)
-		lp_config_set_string(lc->config,"sip","media_encryption","srtp");
-	else if (menc == LinphoneMediaEncryptionZRTP)
-		lp_config_set_string(lc->config,"sip","media_encryption","zrtp");
-	else
-		lp_config_set_string(lc->config,"sip","media_encryption","none");
+int linphone_core_set_media_encryption(LinphoneCore *lc, enum LinphoneMediaEncryption menc) {
+	const char *type="none";
+	int ret=0;
+	if (menc == LinphoneMediaEncryptionSRTP){
+		if (!ortp_srtp_supported()){
+			ms_warning("SRTP not supported by library.");
+			type="none";
+			ret=-1;
+		}else type="srtp";
+	}else if (menc == LinphoneMediaEncryptionZRTP){
+		if (!ortp_zrtp_available()){
+			ms_warning("ZRTP not supported by library.");
+			type="none";
+			ret=-1;
+		}else type="zrtp";
+	}
+	lp_config_set_string(lc->config,"sip","media_encryption",type);
+	return ret;
 }
 
 LinphoneMediaEncryption linphone_core_get_media_encryption(LinphoneCore *lc) {
diff --git a/coreapi/linphonecore.h b/coreapi/linphonecore.h
index 047e6792b..f6da27f9d 100644
--- a/coreapi/linphonecore.h
+++ b/coreapi/linphonecore.h
@@ -1046,8 +1046,8 @@ bool_t linphone_core_media_encryption_supported(const LinphoneCore *lc, Linphone
 /**
  * Choose media encryption policy to be used for RTP packets
  */
-void linphone_core_set_media_encryption(LinphoneCore *lc, enum LinphoneMediaEncryption menc);
-enum LinphoneMediaEncryption linphone_core_get_media_encryption(LinphoneCore *lc);
+int linphone_core_set_media_encryption(LinphoneCore *lc, enum LinphoneMediaEncryption menc);
+LinphoneMediaEncryption linphone_core_get_media_encryption(LinphoneCore *lc);
 
 bool_t linphone_core_is_media_encryption_mandatory(LinphoneCore *lc);
 /**
diff --git a/gtk/parameters.ui b/gtk/parameters.ui
index d853a4bb0..400622632 100644
--- a/gtk/parameters.ui
+++ b/gtk/parameters.ui
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <interface>
-  <requires lib="gtk+" version="2.16"/>
+  <requires lib="gtk+" version="2.22"/>
   <object class="GtkAdjustment" id="adjustment1">
     <property name="lower">500</property>
     <property name="upper">3001</property>
@@ -53,6 +53,7 @@
     <property name="step_increment">1</property>
     <property name="page_increment">10</property>
   </object>
+  <object class="GtkListStore" id="liststore1"/>
   <object class="GtkListStore" id="model1">
     <columns>
       <!-- column-name gchararray -->
@@ -406,13 +407,10 @@
                               </packing>
                             </child>
                             <child>
-                              <object class="GtkComboBoxText" id="media_encryption_combo">
+                              <object class="GtkComboBox" id="media_encryption_combo">
                                 <property name="visible">True</property>
                                 <property name="can_focus">False</property>
                                 <property name="active">0</property>
-                                <items>
-                                  <item translatable="yes">None</item>
-                                </items>
                               </object>
                               <packing>
                                 <property name="left_attach">1</property>
diff --git a/gtk/propertybox.c b/gtk/propertybox.c
index aece58048..8bacff9f5 100644
--- a/gtk/propertybox.c
+++ b/gtk/propertybox.c
@@ -804,7 +804,7 @@ void linphone_gtk_ui_level_toggled(GtkWidget *w) {
 }
 
 static void linphone_gtk_media_encryption_changed(GtkWidget *combo){
-	const char *selected=gtk_combo_box_get_active_text(GTK_COMBO_BOX(combo));
+	char *selected=gtk_combo_box_get_active_text(GTK_COMBO_BOX(combo));
 	LinphoneCore *lc=linphone_gtk_get_core();
 	if (selected!=NULL){
 		if (strcasecmp(selected,"SRTP")==0)
@@ -812,6 +812,7 @@ static void linphone_gtk_media_encryption_changed(GtkWidget *combo){
 		else if (strcasecmp(selected,"ZRTP")==0)
 			linphone_core_set_media_encryption(lc,LinphoneMediaEncryptionZRTP);
 		else linphone_core_set_media_encryption(lc,LinphoneMediaEncryptionNone);
+		g_free(selected);
 	}else g_warning("gtk_combo_box_get_active_text() returned NULL");
 }
 
@@ -820,14 +821,28 @@ static void linphone_gtk_show_media_encryption(GtkWidget *pb){
 	GtkWidget *combo=linphone_gtk_get_widget(pb,"media_encryption_combo");
 	bool_t no_enc=TRUE;
 	int srtp_id=-1,zrtp_id=-1;
-
+	GtkTreeModel *model;
+	GtkListStore *store;
+	GtkTreeIter iter;
+	GtkCellRenderer *renderer=gtk_cell_renderer_text_new();
+	
+	model=GTK_TREE_MODEL((store=gtk_list_store_new(1,G_TYPE_STRING)));
+	gtk_combo_box_set_model(GTK_COMBO_BOX(combo),model);
+	gtk_cell_layout_pack_start(GTK_CELL_LAYOUT(combo),renderer,TRUE);
+	gtk_cell_layout_set_attributes(GTK_CELL_LAYOUT(combo),renderer,"text",0,NULL);
+	
+	gtk_list_store_append(store,&iter);
+	gtk_list_store_set(store,&iter,0,_("None"),-1);
+	
 	if (linphone_core_media_encryption_supported(lc,LinphoneMediaEncryptionSRTP)){
-		gtk_combo_box_text_append_text(GTK_COMBO_BOX_TEXT(combo),_("SRTP"));
+		gtk_list_store_append(store,&iter);
+		gtk_list_store_set(store,&iter,0,_("SRTP"),-1);
 		srtp_id=1;
 		no_enc=FALSE;
 	}
 	if (linphone_core_media_encryption_supported(lc,LinphoneMediaEncryptionZRTP)){
-		gtk_combo_box_text_append_text(GTK_COMBO_BOX_TEXT(combo),_("ZRTP"));
+		gtk_list_store_append(store,&iter);
+		gtk_list_store_set(store,&iter,0,_("ZRTP"),-1);
 		no_enc=FALSE;
 		if (srtp_id!=-1) zrtp_id=2;
 		else zrtp_id=1;
@@ -851,6 +866,7 @@ static void linphone_gtk_show_media_encryption(GtkWidget *pb){
 		}
 		g_signal_connect(G_OBJECT(combo),"changed",(GCallback)linphone_gtk_media_encryption_changed,NULL);
 	}
+	g_object_unref(G_OBJECT(model));
 }
 
 void linphone_gtk_show_parameters(void){