diff --git a/include/osg/GraphicsContext b/include/osg/GraphicsContext
index 6f62e8bf4..16a9671cf 100644
--- a/include/osg/GraphicsContext
+++ b/include/osg/GraphicsContext
@@ -29,24 +29,24 @@ class OSG_EXPORT GraphicsContext : public Object
     
         struct OSG_EXPORT ScreenIdentifier
         {
-            ScreenIdentifier():
-                displayNum(0),
-                screenNum(0) {}
+            ScreenIdentifier();
 
-            ScreenIdentifier(unsigned int in_screenNum):
-                displayNum(0),
-                screenNum(in_screenNum) {}
+            ScreenIdentifier(int in_screenNum);
 
-            ScreenIdentifier(const std::string& in_hostName,unsigned int in_displayNum, unsigned int in_screenNum):
-                hostName(in_hostName),
-                displayNum(in_displayNum),
-                screenNum(in_screenNum) {}
-                
+            ScreenIdentifier(const std::string& in_hostName,int in_displayNum, int in_screenNum);
+            
+            /** Return the display name in the form hostName::displayNum:screenNum. */    
             std::string displayName() const;
+            
+            /** Read the DISPLAY environmental variable, and set the ScreenIdentifier accordingly.*/
+            void readDISPLAY();
+            
+            /** Set the screenIndentifier from the displayName string.*/
+            void setScreenIdentifier(const std::string& displayName);
 
             std::string  hostName;
-            unsigned int displayNum;
-            unsigned int screenNum;
+            int displayNum;
+            int screenNum;
         };
     
         /** GraphicsContext Traits object provides the specification of what type of graphics context is required.*/
@@ -138,6 +138,7 @@ class OSG_EXPORT GraphicsContext : public Object
         /** Callback to be implemented to provide access to Windowing API's ability to create Windows/pbuffers.*/
         struct WindowingSystemInterface : public osg::Referenced
         {
+        
             virtual unsigned int getNumScreens(const ScreenIdentifier& screenIdentifier = ScreenIdentifier()) = 0;
 
             virtual void getScreenResolution(const ScreenIdentifier& screenIdentifier, unsigned int& width, unsigned int& height) = 0;
diff --git a/include/osg/View b/include/osg/View
index c74ea395f..dca402e83 100644
--- a/include/osg/View
+++ b/include/osg/View
@@ -132,7 +132,7 @@ class OSG_EXPORT View : public osg::Object
     
         virtual ~View();
         
-        virtual osg::GraphicsOperation* createRenderer(osg::Camera* camera) { return 0; }
+        virtual osg::GraphicsOperation* createRenderer(osg::Camera*) { return 0; }
 
         osg::ref_ptr<osg::Stats>    _stats;
         
diff --git a/src/osg/GraphicsContext.cpp b/src/osg/GraphicsContext.cpp
index cc5e63139..277673c79 100644
--- a/src/osg/GraphicsContext.cpp
+++ b/src/osg/GraphicsContext.cpp
@@ -59,6 +59,18 @@ GraphicsContext* GraphicsContext::createGraphicsContext(Traits* traits)
         return 0;    
 }
 
+GraphicsContext::ScreenIdentifier::ScreenIdentifier():
+    displayNum(0),
+    screenNum(0) {}
+
+GraphicsContext::ScreenIdentifier::ScreenIdentifier(int in_screenNum):
+    displayNum(0),
+    screenNum(in_screenNum) {}
+
+GraphicsContext::ScreenIdentifier::ScreenIdentifier(const std::string& in_hostName,int in_displayNum, int in_screenNum):
+    hostName(in_hostName),
+    displayNum(in_displayNum),
+    screenNum(in_screenNum) {}
 
 std::string GraphicsContext::ScreenIdentifier::displayName() const
 {
@@ -67,6 +79,60 @@ std::string GraphicsContext::ScreenIdentifier::displayName() const
     return ostr.str();
 }
 
+void GraphicsContext::ScreenIdentifier::readDISPLAY()
+{
+    const char* ptr = 0;
+    if ((ptr=getenv("DISPLAY")) != 0)
+    {
+        setScreenIdentifier(ptr);
+    }
+}
+
+void GraphicsContext::ScreenIdentifier::setScreenIdentifier(const std::string& displayName)
+{
+    std::string::size_type colon = displayName.find_last_of(':');
+    std::string::size_type point = displayName.find_last_of('.');
+    
+    if (point!=std::string::npos && 
+        colon==std::string::npos && 
+        point < colon) point = std::string::npos;
+
+    if (colon==std::string::npos)
+    {
+        hostName = "";
+    }
+    else
+    {
+        hostName = displayName.substr(0,colon);
+    }
+    
+    std::string::size_type startOfDisplayNum = (colon==std::string::npos) ? 0 : colon+1;
+    std::string::size_type endOfDisplayNum = (point==std::string::npos) ?  displayName.size() : point;
+
+    if (startOfDisplayNum<endOfDisplayNum)
+    {
+        displayNum = atoi(displayName.substr(startOfDisplayNum,endOfDisplayNum-startOfDisplayNum).c_str());
+    }
+    else
+    {
+        displayNum = -1;
+    }
+
+    if (point!=std::string::npos && point+1<displayName.size())
+    {
+        screenNum = atoi(displayName.substr(point+1,displayName.size()-point-1).c_str());
+    }
+    else
+    {
+        screenNum = -1;
+    }
+
+#if 0    
+    osg::notify(osg::NOTICE)<<"   hostName ["<<hostName<<"]"<<std::endl;
+    osg::notify(osg::NOTICE)<<"   displayNum "<<displayNum<<std::endl;
+    osg::notify(osg::NOTICE)<<"   screenNum "<<screenNum<<std::endl;
+#endif
+}
 
 class ContextData
 {
diff --git a/src/osgViewer/View.cpp b/src/osgViewer/View.cpp
index bad1ebf6d..638fab2ae 100644
--- a/src/osgViewer/View.cpp
+++ b/src/osgViewer/View.cpp
@@ -266,13 +266,24 @@ void View::setUpViewAcrossAllScreens()
     double fovy, aspectRatio, zNear, zFar;        
     _camera->getProjectionMatrixAsPerspective(fovy, aspectRatio, zNear, zFar);
 
-    unsigned int numScreens = wsi->getNumScreens();
+    osg::GraphicsContext::ScreenIdentifier si;
+    si.readDISPLAY();
+    
+    // displayNum has not been set so reset it to 0.
+    if (si.displayNum<0) si.displayNum = 0;
+    
+    unsigned int numScreens = wsi->getNumScreens(si);
     if (numScreens==1)
     {
+        if (si.screenNum<0) si.screenNum = 0;
+    
         unsigned int width, height;
-        wsi->getScreenResolution(osg::GraphicsContext::ScreenIdentifier(0), width, height);
+        wsi->getScreenResolution(si, width, height);
 
         osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
+        traits->hostName = si.hostName;
+        traits->displayNum = si.displayNum;
+        traits->screenNum = si.screenNum;
         traits->x = 0;
         traits->y = 0;
         traits->width = width;
@@ -336,10 +347,15 @@ void View::setUpViewAcrossAllScreens()
     
         for(unsigned int i=0; i<numScreens; ++i)
         {
+            si.screenNum = i;
+        
             unsigned int width, height;
-            wsi->getScreenResolution(osg::GraphicsContext::ScreenIdentifier(i), width, height);
+            wsi->getScreenResolution(si, width, height);
 
             osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
+            traits->hostName = si.hostName;
+            traits->displayNum = si.displayNum;
+            traits->screenNum = si.screenNum;
             traits->screenNum = i;
             traits->x = 0;
             traits->y = 0;
@@ -410,6 +426,10 @@ void View::setUpViewInWindow(int x, int y, int width, int height, unsigned int s
     osg::DisplaySettings* ds = _displaySettings.valid() ? _displaySettings.get() : osg::DisplaySettings::instance();
 
     osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
+
+    traits->readDISPLAY();
+    if (traits->displayNum<0) traits->displayNum = 0;
+    
     traits->screenNum = screenNum;
     traits->x = x;
     traits->y = y;
@@ -471,11 +491,21 @@ void View::setUpViewOnSingleScreen(unsigned int screenNum)
 
     osg::DisplaySettings* ds = _displaySettings.valid() ? _displaySettings.get() : osg::DisplaySettings::instance();
 
+    osg::GraphicsContext::ScreenIdentifier si;
+    si.readDISPLAY();
+    
+    // displayNum has not been set so reset it to 0.
+    if (si.displayNum<0) si.displayNum = 0;
+
+    si.screenNum = screenNum;
+
     unsigned int width, height;
-    wsi->getScreenResolution(osg::GraphicsContext::ScreenIdentifier(screenNum), width, height);
+    wsi->getScreenResolution(si, width, height);
 
     osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
-    traits->screenNum = screenNum;
+    traits->hostName = si.hostName;
+    traits->displayNum = si.displayNum;
+    traits->screenNum = si.screenNum;
     traits->x = 0;
     traits->y = 0;
     traits->width = width;