diff --git a/gtk2_ardour/luainstance.cc b/gtk2_ardour/luainstance.cc
index c02e864833..6f33bf9f25 100644
--- a/gtk2_ardour/luainstance.cc
+++ b/gtk2_ardour/luainstance.cc
@@ -1113,9 +1113,10 @@ LuaInstance::register_classes (lua_State* L, bool sandbox)
 
 		.addCFunction ("actionlist", &lua_actionlist)
 
-
 		.beginClass <UIConfiguration> ("UIConfiguration")
+		.addFunction ("set_modifier", (void (UIConfiguration::*)(std::string const&, std::string const&))&UIConfiguration::set_modifier)
 #undef  UI_CONFIG_VARIABLE
+
 #define UI_CONFIG_VARIABLE(Type,var,name,value) \
 		.addFunction ("get_" # var, &UIConfiguration::get_##var) \
 		.addFunction ("set_" # var, &UIConfiguration::set_##var) \
diff --git a/gtk2_ardour/ui_config.cc b/gtk2_ardour/ui_config.cc
index 9a82e5f43f..c09e4581f7 100644
--- a/gtk2_ardour/ui_config.cc
+++ b/gtk2_ardour/ui_config.cc
@@ -824,6 +824,13 @@ UIConfiguration::set_modifier (string const & name, SVAModifier svam)
 	ColorsChanged (); /* EMIT SIGNAL */
 }
 
+void
+UIConfiguration::set_modifier (string const & name, string const & mod_str)
+{
+	SVAModifier svam (mod_str);
+	set_modifier (name, svam);
+}
+
 void
 UIConfiguration::load_rc_file (bool themechange, bool allow_own)
 {
diff --git a/gtk2_ardour/ui_config.h b/gtk2_ardour/ui_config.h
index 2396a52141..df3e571015 100644
--- a/gtk2_ardour/ui_config.h
+++ b/gtk2_ardour/ui_config.h
@@ -81,6 +81,7 @@ public:
 	void set_alias (std::string const& name, std::string const& alias);
 	void set_color (const std::string& name, Gtkmm2ext::Color);
 	void set_modifier (std::string const&, Gtkmm2ext::SVAModifier svam);
+	void set_modifier (std::string const& name, std::string const& mod_str);
 
 	Gtkmm2ext::Color quantized (Gtkmm2ext::Color) const;