PublisherFactory.cppのdestroy()メソッドを下記のように変更。

m$ svn diff PublisherFactory.cpp 
Index: PublisherFactory.cpp
===================================================================
--- PublisherFactory.cpp    (リビジョン 1212)
+++ PublisherFactory.cpp    (作業コピー)
@@ -66,7 +66,9 @@
    */
   void PublisherFactory::destroy(PublisherBase* publisher)
   {
-    publisher->release();
-    delete publisher;
+    if (publisher != NULL) {
+      publisher->release();
+      delete publisher;
+    }
   }