Index: libs/ardour/ardour/ladspa_plugin.h
===================================================================
--- libs/ardour/ardour/ladspa_plugin.h	(revision 11500)
+++ libs/ardour/ardour/ladspa_plugin.h	(working copy)
@@ -113,7 +113,14 @@
 	LADSPA_Properties           properties() const                { return _descriptor->Properties; }
 	uint32_t                    index() const                     { return _index; }
 	const char *                copyright() const                 { return _descriptor->Copyright; }
-	LADSPA_PortDescriptor       port_descriptor(uint32_t i) const { return _descriptor->PortDescriptors[i]; }
+	LADSPA_PortDescriptor       port_descriptor(uint32_t i) const {
+		if (i < _descriptor->PortCount) {		
+			return _descriptor->PortDescriptors[i];
+		}
+		std::cerr << "LadspaPlugin::port_descriptor(" << i << ") out of range! " << _descriptor->PortCount << std::endl;
+		return 0;
+		
+	}
 	const LADSPA_PortRangeHint* port_range_hints() const          { return _descriptor->PortRangeHints; }
 	const char * const *        port_names() const                { return _descriptor->PortNames; }