diff --git a/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java b/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
index e904e617c..f6f6df0f1 100644
--- a/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
+++ b/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
@@ -76,6 +76,7 @@ import org.openide.util.Lookup;
 import org.openide.util.LookupEvent;
 import org.openide.util.LookupListener;
 import org.openide.util.NbBundle.Messages;
+import org.openide.util.WeakListeners;
 import org.openide.util.lookup.InstanceContent;
 import org.openide.windows.TopComponent;
 
@@ -484,7 +485,7 @@ public final class MatDefEditorlElement extends JPanel implements MultiViewEleme
         Dot leftDot = findConnectPoint(mapping.getLeftNameSpace(), mapping.getLeftVar(), true);
         Dot rightDot = findConnectPoint(mapping.getRightNameSpace(), mapping.getRightVar(), false);
         Connection conn = diagram1.connect(leftDot, rightDot);
-        mapping.addPropertyChangeListener(conn);
+        mapping.addPropertyChangeListener(WeakListeners.propertyChange(conn, mapping));
         conn.makeKey(mapping, diagram1.getCurrentTechniqueName());
     }
 
diff --git a/sdk/jme3-materialeditor/src/com/jme3/gde/materials/MaterialPreviewRenderer.java b/sdk/jme3-materialeditor/src/com/jme3/gde/materials/MaterialPreviewRenderer.java
index 6ff461c43..96d005577 100644
--- a/sdk/jme3-materialeditor/src/com/jme3/gde/materials/MaterialPreviewRenderer.java
+++ b/sdk/jme3-materialeditor/src/com/jme3/gde/materials/MaterialPreviewRenderer.java
@@ -94,11 +94,10 @@ public class MaterialPreviewRenderer implements SceneListener {
         if (!init) {
             init();
         }
-        final DesktopAssetManager assetManager = (DesktopAssetManager) SceneApplication.getApplication().getAssetManager();
         SceneApplication.getApplication().enqueue(new Callable<Material>() {
 
             public Material call() throws Exception {
-                final Material mat = reloadMaterial(m, assetManager);
+                final Material mat = reloadMaterial(m);
                 if (mat != null) {
                     java.awt.EventQueue.invokeLater(new Runnable() {
                         public void run() {
@@ -124,11 +123,9 @@ public class MaterialPreviewRenderer implements SceneListener {
 
     }
     
-      public Material reloadMaterial(Material mat, DesktopAssetManager assetManager) {
-
-        //MaterialKey key = new MaterialKey(mat.getMaterialDef().getAssetName());
-        ((ProjectAssetManager)mat.getMaterialDef().getAssetManager()).clearCache();
-        //assetManager.clearCache();
+      public Material reloadMaterial(Material mat) {
+       
+        ((ProjectAssetManager)mat.getMaterialDef().getAssetManager()).clearCache();   
         
         //creating a dummy mat with the mat def of the mat to reload
         Material dummy = new Material(mat.getMaterialDef());