diff --git a/core/AmPlugIn.cpp b/core/AmPlugIn.cpp
index a63f4a9d..564dae5d 100644
--- a/core/AmPlugIn.cpp
+++ b/core/AmPlugIn.cpp
@@ -108,10 +108,18 @@ AmPlugIn::AmPlugIn()
 {
 }
 
+static std::set<AmPluginFactory*> deleted_factories;
+static std::set<string> deleted_factories_names;
+
 static void delete_plugin_factory(std::pair<string, AmPluginFactory*> pf)
 {
-  DBG("deleting plug-in factory: %s\n", pf.first.c_str());
-  delete pf.second;
+  if ((deleted_factories.find(pf.second) == deleted_factories.end()) &&
+      (deleted_factories_names.find(pf.first) == deleted_factories_names.end())) {
+    DBG("deleting plug-in factory: %s\n", pf.first.c_str());
+    deleted_factories.insert(pf.second);
+    deleted_factories_names.insert(pf.first);
+    delete pf.second;
+  }
 }
 
 AmPlugIn::~AmPlugIn()