diff --git a/designer-base/src/com/fr/design/mainframe/DesignerFrameFileDealerPane.java b/designer-base/src/com/fr/design/mainframe/DesignerFrameFileDealerPane.java
index c35e7e359..fddf359c5 100644
--- a/designer-base/src/com/fr/design/mainframe/DesignerFrameFileDealerPane.java
+++ b/designer-base/src/com/fr/design/mainframe/DesignerFrameFileDealerPane.java
@@ -53,7 +53,7 @@ public class DesignerFrameFileDealerPane extends JPanel implements FileToolbarSt
     
     private static final String FILE = "file";
     
-    private static DesignerFrameFileDealerPane THIS;
+    private static volatile DesignerFrameFileDealerPane THIS;
     
     private CardLayout card;
     
@@ -81,11 +81,15 @@ public class DesignerFrameFileDealerPane extends JPanel implements FileToolbarSt
     
         selectedOperation.refresh();
     }
-    
+
     public static final DesignerFrameFileDealerPane getInstance() {
-        
+
         if (THIS == null) {
-            THIS = new DesignerFrameFileDealerPane();
+            synchronized (DesignerFrameFileDealerPane.class) {
+                if (THIS == null) {
+                    THIS = new DesignerFrameFileDealerPane();
+                }
+            }
         }
         return THIS;
     }
diff --git a/designer-base/src/com/fr/design/mainframe/EastRegionContainerPane.java b/designer-base/src/com/fr/design/mainframe/EastRegionContainerPane.java
index ef8729ddc..0adf8785c 100644
--- a/designer-base/src/com/fr/design/mainframe/EastRegionContainerPane.java
+++ b/designer-base/src/com/fr/design/mainframe/EastRegionContainerPane.java
@@ -30,7 +30,7 @@ import java.util.Map;
 import java.util.Set;
 
 public class EastRegionContainerPane extends UIEastResizableContainer {
-    private static EastRegionContainerPane THIS;
+    private static volatile EastRegionContainerPane THIS;
     private Map<String, PropertyItem> propertyItemMap;
     private CardLayout propertyCard;
     private JPanel leftPane;
@@ -84,13 +84,17 @@ public class EastRegionContainerPane extends UIEastResizableContainer {
      */
     public static EastRegionContainerPane getInstance() {
         if (THIS == null) {
-            THIS = new EastRegionContainerPane();
-            THIS.setLastContainerWidth(DesignerEnvManager.getEnvManager().getLastEastRegionContainerWidth());
+            synchronized (EastRegionContainerPane.class) {
+                if (THIS == null) {
+                    THIS = new EastRegionContainerPane();
+                    THIS.setLastContainerWidth(DesignerEnvManager.getEnvManager().getLastEastRegionContainerWidth());
+                }
+            }
         }
         return THIS;
     }
 
-    public EastRegionContainerPane() {
+    private EastRegionContainerPane() {
         super();
         initPropertyItemList();
         defaultPane = getDefaultPane(Inter.getLocText("FR-Designer_No_Settings_Available"));
diff --git a/designer-realize/src/com/fr/design/mainframe/CellElementPropertyPane.java b/designer-realize/src/com/fr/design/mainframe/CellElementPropertyPane.java
index 68b1134f7..f87ff4a83 100644
--- a/designer-realize/src/com/fr/design/mainframe/CellElementPropertyPane.java
+++ b/designer-realize/src/com/fr/design/mainframe/CellElementPropertyPane.java
@@ -65,16 +65,20 @@ public class CellElementPropertyPane extends DockingView {
             }
         });
     }
-    
-    
+
+
     public synchronized static CellElementPropertyPane getInstance() {
         if (singleton == null) {
-            singleton = new CellElementPropertyPane();
+            synchronized (CellElementPropertyPane.class) {
+                if (singleton == null) {
+                    singleton = new CellElementPropertyPane();
+                }
+            }
         }
         return singleton;
     }
 
-    private static CellElementPropertyPane singleton;
+    private static volatile CellElementPropertyPane singleton;
 
     private CellElementEditPane cellElementEditPane;