diff --git a/components/resource/bulletshapemanager.cpp b/components/resource/bulletshapemanager.cpp
index c1a7eb8f3..53b08b8be 100644
--- a/components/resource/bulletshapemanager.cpp
+++ b/components/resource/bulletshapemanager.cpp
@@ -141,10 +141,7 @@ osg::ref_ptr<const BulletShape> BulletShapeManager::getShape(const std::string &
             node->accept(visitor);
             shape = visitor.getShape();
             if (!shape)
-            {
-                mCache->addEntryToObjectCache(normalized, NULL);
                 return osg::ref_ptr<BulletShape>();
-            }
         }
 
         mCache->addEntryToObjectCache(normalized, shape);
@@ -158,7 +155,8 @@ osg::ref_ptr<BulletShapeInstance> BulletShapeManager::cacheInstance(const std::s
     mVFS->normalizeFilename(normalized);
 
     osg::ref_ptr<BulletShapeInstance> instance = createInstance(normalized);
-    mInstanceCache->addEntryToObjectCache(normalized, instance.get());
+    if (instance)
+        mInstanceCache->addEntryToObjectCache(normalized, instance.get());
     return instance;
 }
 
diff --git a/components/resource/multiobjectcache.cpp b/components/resource/multiobjectcache.cpp
index 266139f3c..d6639d3ae 100644
--- a/components/resource/multiobjectcache.cpp
+++ b/components/resource/multiobjectcache.cpp
@@ -51,6 +51,11 @@ namespace Resource
 
     void MultiObjectCache::addEntryToObjectCache(const std::string &filename, osg::Object *object)
     {
+        if (!object)
+        {
+            OSG_ALWAYS << " trying to add NULL object to cache for " << filename << std::endl;
+            return;
+        }
         OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_objectCacheMutex);
         _objectCache.insert(std::make_pair(filename, object));
     }
diff --git a/components/resource/objectcache.cpp b/components/resource/objectcache.cpp
index de0fa7a40..e8c082f91 100644
--- a/components/resource/objectcache.cpp
+++ b/components/resource/objectcache.cpp
@@ -34,6 +34,11 @@ ObjectCache::~ObjectCache()
 
 void ObjectCache::addEntryToObjectCache(const std::string& filename, osg::Object* object, double timestamp)
 {
+    if (!object)
+    {
+        OSG_ALWAYS << " trying to add NULL object to cache for " << filename << std::endl;
+        return;
+    }
     OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_objectCacheMutex);
     _objectCache[filename]=ObjectTimeStampPair(object,timestamp);
 }