diff --git a/libs/ardour/luabindings.cc b/libs/ardour/luabindings.cc
index d368eff6ca..822cab4a55 100644
--- a/libs/ardour/luabindings.cc
+++ b/libs/ardour/luabindings.cc
@@ -672,6 +672,7 @@ LuaBindings::common (lua_State* L)
 		.endClass ()
 
 		.beginWSPtrClass <PluginInfo> ("PluginInfo")
+		.addNilPtrConstructor ()
 		.addData ("name", &PluginInfo::name, false)
 		.addData ("category", &PluginInfo::category, false)
 		.addData ("creator", &PluginInfo::creator, false)
@@ -1618,6 +1619,17 @@ LuaBindings::common (lua_State* L)
 		.addConst ("SharePlaylist", ARDOUR::PlaylistDisposition(SharePlaylist))
 		.endNamespace ()
 
+		.beginNamespace ("MidiTrackNameSource")
+		.addConst ("SMFTrackNumber", ARDOUR::MidiTrackNameSource(SMFTrackNumber))
+		.addConst ("SMFTrackName", ARDOUR::MidiTrackNameSource(SMFTrackName))
+		.addConst ("SMFInstrumentName", ARDOUR::MidiTrackNameSource(SMFInstrumentName))
+		.endNamespace ()
+
+		.beginNamespace ("MidiTempoMapDisposition")
+		.addConst ("SMFTempoIgnore", ARDOUR::MidiTrackNameSource(SMFTempoIgnore))
+		.addConst ("SMFTempoUse", ARDOUR::MidiTrackNameSource(SMFTempoUse))
+		.endNamespace ()
+
 		.beginNamespace ("RegionPoint")
 		.addConst ("Start", ARDOUR::RegionPoint(Start))
 		.addConst ("End", ARDOUR::RegionPoint(End))