diff --git a/include/osgDB/DatabaseRevisions b/include/osgDB/DatabaseRevisions
index cfabfc076..6127ae884 100644
--- a/include/osgDB/DatabaseRevisions
+++ b/include/osgDB/DatabaseRevisions
@@ -43,6 +43,8 @@ class OSGDB_EXPORT FileList : public osg::Object
 
         bool removeFile(const std::string& filename);
 
+        void append(FileList* fileList);
+
     protected:
 
         virtual ~FileList();
diff --git a/src/osgDB/DatabaseRevisions.cpp b/src/osgDB/DatabaseRevisions.cpp
index 9749eda6e..7aa050b30 100644
--- a/src/osgDB/DatabaseRevisions.cpp
+++ b/src/osgDB/DatabaseRevisions.cpp
@@ -45,6 +45,17 @@ bool FileList::removeFile(const std::string& filename)
     return true;
 }
 
+void FileList::append(FileList* fileList)
+{
+    for(FileNames::iterator itr = fileList->_files.begin();
+        itr != fileList->_files.end();
+        ++itr)
+    {
+        _files.insert(*itr);
+    }
+}
+
+
 ////////////////////////////////////////////////////////////////////////////////////////////
 //
 // DatabaseRevision