diff --git a/include/osgDB/ImagePager b/include/osgDB/ImagePager
index 3b4ac7376..0564112f7 100644
--- a/include/osgDB/ImagePager
+++ b/include/osgDB/ImagePager
@@ -122,8 +122,10 @@ class OSGDB_EXPORT ImagePager : public osg::NodeVisitor::ImageRequestHandler
 
             void sort();
 
+            unsigned int size() const;
+
             RequestList         _requestList;
-            OpenThreads::Mutex  _requestMutex;
+            mutable OpenThreads::Mutex  _requestMutex;
         };
 
 
diff --git a/src/osgDB/ImagePager.cpp b/src/osgDB/ImagePager.cpp
index 4fea58e6f..19a45879c 100644
--- a/src/osgDB/ImagePager.cpp
+++ b/src/osgDB/ImagePager.cpp
@@ -35,13 +35,20 @@ struct ImagePager::SortFileRequestFunctor
 
 /////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //
-//  ReadQueue
+//  RequestQueue
 //
 void ImagePager::RequestQueue::sort()
 {
     std::sort(_requestList.begin(),_requestList.end(),SortFileRequestFunctor());
 }
 
+unsigned int ImagePager::RequestQueue::size() const
+{
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_requestMutex);
+    return _requestList.size();
+}
+
+
 
 /////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //
@@ -74,9 +81,12 @@ void ImagePager::ReadQueue::clear()
 void ImagePager::ReadQueue::add(ImagePager::ImageRequest* databaseRequest)
 {
     OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_requestMutex);
+    
     _requestList.push_back(databaseRequest);
     databaseRequest->_requestQueue = this;
 
+    OSG_INFO<<"ImagePager::ReadQueue::add(..), size()="<<size()<<std::endl;
+
     updateBlock();
 }