diff --git a/include/osgDB/Registry b/include/osgDB/Registry
index b8333040a..106f3443c 100644
--- a/include/osgDB/Registry
+++ b/include/osgDB/Registry
@@ -385,6 +385,8 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         /** Get the SharedStateManager. Return 0 if no SharedStateManager has been assigned.*/
         SharedStateManager* getSharedStateManager() { return _sharedStateManager.get(); }
 
+        /** Add an Archive extension.*/
+        void addArchiveExtension(const std::string ext);
 
     protected:
 
@@ -394,6 +396,7 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         typedef std::map< std::string, osg::ref_ptr<DotOsgWrapper> >    DotOsgWrapperMap;
         typedef std::vector< osg::ref_ptr<DynamicLibrary> >             DynamicLibraryList;
         typedef std::map< std::string, std::string>                     ExtensionAliasMap;
+        typedef std::vector< std::string>                               ArchiveExtensionList;
         
         typedef std::pair<osg::ref_ptr<osg::Object>, double >           ObjectTimeStampPair;
         typedef std::map<std::string, ObjectTimeStampPair >             ObjectCache;
@@ -489,7 +492,8 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         
         ArchiveCache                            _archiveCache;
         OpenThreads::Mutex                      _archiveCacheMutex;
-        
+
+        ArchiveExtensionList                    _archiveExtList;
         
         osg::ref_ptr<DatabasePager>             _databasePager;
         osg::ref_ptr<SharedStateManager>        _sharedStateManager;
diff --git a/src/osgDB/Archive.cpp b/src/osgDB/Archive.cpp
index c9325f450..8fd76c516 100644
--- a/src/osgDB/Archive.cpp
+++ b/src/osgDB/Archive.cpp
@@ -29,6 +29,13 @@ osgDB::Archive* osgDB::openArchive(const std::string& filename, Archive::Archive
 
 osgDB::Archive* osgDB::openArchive(const std::string& filename, Archive::ArchiveStatus status, unsigned int indexBlockSizeHint,ReaderWriter::Options* options)
 {
+    // ensure archive extension is in the registry list
+    std::string::size_type dot = filename.find_last_of('.');
+    if (dot != std::string::npos)
+    {
+        std::string ext = filename.substr(dot+1);
+        Registry::instance()->addArchiveExtension(ext);
+    }
     ReaderWriter::ReadResult result = osgDB::Registry::instance()->openArchive(filename, status, indexBlockSizeHint, options);
     return result.takeArchive();
 }
diff --git a/src/osgDB/Registry.cpp b/src/osgDB/Registry.cpp
index 2f71644b9..7f5512eb0 100644
--- a/src/osgDB/Registry.cpp
+++ b/src/osgDB/Registry.cpp
@@ -136,6 +136,9 @@ Registry::Registry()
 
     _createNodeFromImage = false;
     _openingLibrary = false;
+
+    // add default osga archive extension
+    _archiveExtList.push_back("osga");
     
     initFilePathLists();
 
@@ -1291,30 +1294,47 @@ struct Registry::ReadArchiveFunctor : public Registry::ReadFunctor
 
 };
 
+void Registry::addArchiveExtension(const std::string ext)
+{
+    for(ArchiveExtensionList::iterator aitr=_archiveExtList.begin();
+        aitr!=_archiveExtList.end();
+        ++aitr)
+    {
+        if ( (*aitr) == ext)   // extension already in archive extension list
+            return;
+    }
+    _archiveExtList.push_back(ext);
+};
+
 ReaderWriter::ReadResult Registry::read(const ReadFunctor& readFunctor)
 {
-    std::string archiveName(".osga");
-
-    std::string::size_type positionArchive = readFunctor._filename.find(archiveName+'/');
-    if (positionArchive==std::string::npos) positionArchive = readFunctor._filename.find(archiveName+'\\');
-    if (positionArchive!=std::string::npos)
+    for(ArchiveExtensionList::iterator aitr=_archiveExtList.begin();
+        aitr!=_archiveExtList.end();
+        ++aitr)
     {
-        std::string archiveName(readFunctor._filename.substr(0,positionArchive+5));
-        std::string fileName(readFunctor._filename.substr(positionArchive+6,std::string::npos));
-        osg::notify(osg::INFO)<<"Contains archive : "<<readFunctor._filename<<std::endl;
-        osg::notify(osg::INFO)<<"         archive : "<<archiveName<<std::endl;
-        osg::notify(osg::INFO)<<"         filename : "<<fileName<<std::endl;
-        
-        ReaderWriter::ReadResult result = openArchiveImplementation(archiveName,ReaderWriter::READ, 4096, readFunctor._options);
-        
-        if (!result.validArchive()) return result;
+        std::string archiveName = "." + (*aitr);
 
-        osgDB::Archive* archive = result.getArchive();
+        std::string::size_type positionArchive = readFunctor._filename.find(archiveName+'/');
+        if (positionArchive==std::string::npos) positionArchive = readFunctor._filename.find(archiveName+'\\');
+        if (positionArchive!=std::string::npos)
+        {
+            std::string archiveName(readFunctor._filename.substr(0,positionArchive+5));
+            std::string fileName(readFunctor._filename.substr(positionArchive+6,std::string::npos));
+            osg::notify(osg::INFO)<<"Contains archive : "<<readFunctor._filename<<std::endl;
+            osg::notify(osg::INFO)<<"         archive : "<<archiveName<<std::endl;
+            osg::notify(osg::INFO)<<"         filename : "<<fileName<<std::endl;
         
-        osg::ref_ptr<ReaderWriter::Options> options = new ReaderWriter::Options;
-        options->setDatabasePath(archiveName);
+            ReaderWriter::ReadResult result = openArchiveImplementation(archiveName,ReaderWriter::READ, 4096, readFunctor._options);
+        
+            if (!result.validArchive()) return result;
 
-        return archive->readObject(fileName,options.get());
+            osgDB::Archive* archive = result.getArchive();
+        
+            osg::ref_ptr<ReaderWriter::Options> options = new ReaderWriter::Options;
+            options->setDatabasePath(archiveName);
+
+            return archive->readObject(fileName,options.get());
+        }
     }
 
     // if filename contains archive