Index: EMFModelValidationPlugin.java
===================================================================
RCS file: /cvsroot/modeling/org.eclipse.emf/org.eclipse.emf.validation/plugins/org.eclipse.emf.validation/src/org/eclipse/emf/validation/internal/EMFModelValidationPlugin.java,v
retrieving revision 1.6
diff -u -r1.6 EMFModelValidationPlugin.java
--- EMFModelValidationPlugin.java	5 Oct 2008 22:12:16 -0000	1.6
+++ EMFModelValidationPlugin.java	23 Jul 2009 07:40:05 -0000
@@ -15,7 +15,9 @@
 package org.eclipse.emf.validation.internal;
 
 import java.util.Collection;
+import java.util.Dictionary;
 import java.util.HashMap;
+import java.util.Hashtable;
 import java.util.Iterator;
 import java.util.Map;
 
@@ -26,6 +28,8 @@
 import org.eclipse.emf.common.EMFPlugin;
 import org.eclipse.emf.common.util.ResourceLocator;
 import org.eclipse.emf.validation.internal.l10n.ValidationMessages;
+import org.eclipse.osgi.service.debug.DebugOptions;
+import org.eclipse.osgi.service.debug.DebugOptionsListener;
 import org.eclipse.osgi.util.NLS;
 import org.osgi.framework.BundleContext;
 
@@ -213,7 +217,7 @@
 	 * 
 	 * @author Christian W. Damus (cdamus)
 	 */
-	public static class Implementation extends EMFPlugin.EclipsePlugin {
+	public static class Implementation extends EMFPlugin.EclipsePlugin implements DebugOptionsListener {
 		/**
 		 * Track extensions for extension points defined in this bundle.
 		 */
@@ -237,6 +241,11 @@
 			super.start(context);
 			
 			extensionTracker = new ExtensionTracker();
+			
+			// register listener that is notified whenever debug options change
+			Dictionary<String, Object> props = new Hashtable<String, Object>(4);
+			props.put(DebugOptions.LISTENER_SYMBOLICNAME, getPluginId());
+			context.registerService(DebugOptionsListener.class.getName(), this, props);
 		}
 		
 		@Override
@@ -246,6 +255,10 @@
 			
 			super.stop(context);
 		}
+		
+		public void optionsChanged(DebugOptions options) {
+			Tracing.invalidateCache();
+		}
 	}
 	
     public static class Tracing {
@@ -255,13 +268,31 @@
     	private static final Map<String, Boolean> cachedOptions = new HashMap<String, Boolean>();
 
     	/**
+    	 * The cached Boolean value indicating whether tracing is enabled. 
+    	 */
+    	private static Boolean debugging = null;
+    	
+    	/**
+    	 * Invalidates the cached debug options and the cached Boolean value
+    	 * indicating whether tracing is enabled.
+    	 */
+    	protected static void invalidateCache() {
+    		cachedOptions.clear();
+    		debugging = null;
+    	}
+    	
+    	/**
     	 * Retrieves a Boolean value indicating whether tracing is enabled.
     	 * 
     	 * @return Whether tracing is enabled for the plug-in.
     	 * 
     	 */
     	protected static boolean shouldTrace() {
-    		return plugin.isDebugging();
+    		if (debugging == null) {    			
+    			debugging = plugin.isDebugging();
+    		}
+    		
+    		return debugging.booleanValue();
     	}
 
     	/**