diff --git a/gtk2_ardour/main.cc b/gtk2_ardour/main.cc
index 51c1928d20..c4b9b9a897 100644
--- a/gtk2_ardour/main.cc
+++ b/gtk2_ardour/main.cc
@@ -83,7 +83,10 @@ fixup_bundle_environment ()
 	Glib::ustring path;
 	const char *cstr = getenv ("PATH");
 
-	/* ensure that we find any bundled executables (e.g. JACK) */
+	/* ensure that we find any bundled executables (e.g. JACK),
+	   and find them before any instances of the same name
+	   elsewhere in PATH
+	*/
 
 	path = dir_path;
 	if (cstr) {
@@ -118,8 +121,10 @@ fixup_bundle_environment ()
 	if (cstr) {
 		path = cstr;
 		path += ':';
+	} else {
+		path = "";
 	}
-	path = dir_path;
+	path += dir_path;
 	path += "/../Plugins";
 	
 	setenv ("LADSPA_PATH", path.c_str(), 1);
@@ -128,8 +133,10 @@ fixup_bundle_environment ()
 	if (cstr) {
 		path = cstr;
 		path += ':';
+	} else {
+		path = "";
 	}
-	path = dir_path;
+	path += dir_path;
 	path += "/../Frameworks";
 	
 	setenv ("VAMP_PATH", path.c_str(), 1);
@@ -138,8 +145,10 @@ fixup_bundle_environment ()
 	if (cstr) {
 		path = cstr;
 		path += ':';
+	} else {
+		path = "";
 	}
-	path = dir_path;
+	path += dir_path;
 	path += "/../Surfaces";
 	
 	setenv ("ARDOUR_CONTROL_SURFACE_PATH", path.c_str(), 1);
@@ -148,8 +157,10 @@ fixup_bundle_environment ()
 	if (cstr) {
 		path = cstr;
 		path += ':';
+	} else {
+		path = "";
 	}
-	path = dir_path;
+	path += dir_path;
 	path += "/../Plugins";
 	
 	setenv ("LV2_PATH", path.c_str(), 1);
@@ -184,8 +195,11 @@ fixup_bundle_environment ()
 			error << string_compose (_("cannot open pango.rc file %1") , path) << endmsg;
 		} else {
 			pangorc << "[Pango]\nModuleFiles=";
-			Glib::ustring mpath = dir_path;
+			Glib::ustring mpath;
+
+			mpath = dir_path;
 			mpath += "/../Resources/pango.modules";
+
 			pangorc << mpath << endl;
 			
 			pangorc.close ();
diff --git a/libs/ardour/plugin_manager.cc b/libs/ardour/plugin_manager.cc
index 6dac06f870..ad94019aad 100644
--- a/libs/ardour/plugin_manager.cc
+++ b/libs/ardour/plugin_manager.cc
@@ -150,9 +150,15 @@ void
 PluginManager::ladspa_refresh ()
 {
 	_ladspa_plugin_info.clear ();
+	static const char *standard_path = "/usr/local/lib64/ladspa:/usr/local/lib/ladspa:/usr/lib64/ladspa:/usr/lib/ladspa:/Library/Audio/Plug-Ins/LADSPA";
+	
+	/* allow LADSPA_PATH to augment, not override standard locations */
 
-	if (ladspa_path.length() == 0) {
-		ladspa_path = "/usr/local/lib64/ladspa:/usr/local/lib/ladspa:/usr/lib64/ladspa:/usr/lib/ladspa:/Library/Audio/Plug-Ins/LADSPA";
+	if (ladspa_path.empty()) {
+		ladspa_path = standard_path;
+	} else {
+		ladspa_path += ":";
+		ladspa_path += standard_path;
 	}
 
 	ladspa_discover_from_path (ladspa_path);
diff --git a/svn_revision.h b/svn_revision.h
index c89592b652..22d9301de8 100644
--- a/svn_revision.h
+++ b/svn_revision.h
@@ -1,4 +1,4 @@
 #ifndef __ardour_svn_revision_h__
 #define __ardour_svn_revision_h__
-static const char* ardour_svn_revision = "3930";
+static const char* ardour_svn_revision = "3963";
 #endif