Index: trunk/src/plugins/sim_ngspice/sim_ngspice.c
===================================================================
--- trunk/src/plugins/sim_ngspice/sim_ngspice.c	(revision 10284)
+++ trunk/src/plugins/sim_ngspice/sim_ngspice.c	(revision 10285)
@@ -595,12 +595,19 @@
 	return 0;
 }
 
+static int on_unload(fgw_obj_t *obj)
+{
+	target_spice->unload(obj);
+	return 0;
+}
+
+
 static const fgw_eng_t fgw_sim_ngspice_eng = {
 	"target_sim_ngspice",
 	csch_c_call_script,
 	NULL,
 	on_load,
-	NULL /* unload */
+	on_unload
 };
 
 int pplg_check_ver_sim_ngspice(int ver_needed) { return 0; }