diff --git a/modules/plugin/base/src/ns4xPlugin.h b/modules/plugin/base/src/ns4xPlugin.h
index c0e97673e51f..b4a1a7dff45e 100644
--- a/modules/plugin/base/src/ns4xPlugin.h
+++ b/modules/plugin/base/src/ns4xPlugin.h
@@ -38,6 +38,7 @@
 #ifndef ns4xPlugin_h__
 #define ns4xPlugin_h__
 
+#include "nsIFactory.h"
 #include "nsIPlugin.h"
 #include "nsIPluginInstancePeer.h"
 #include "nsIWindowlessPlugInstPeer.h"
@@ -116,34 +117,9 @@ public:
   virtual ~ns4xPlugin(void);
 
   NS_DECL_ISUPPORTS
-
-  //nsIFactory interface
-
-  NS_IMETHOD CreateInstance(nsISupports *aOuter,
-                            REFNSIID aIID,
-                            void **aResult);
-
-  NS_IMETHOD LockFactory(PRBool aLock);
-
-  //nsIPlugin interface
-
-  /**
-   * Creates a new plugin instance, based on a MIME type. This
-   * allows different impelementations to be created depending on
-   * the specified MIME type.
-   */
-  NS_IMETHOD CreatePluginInstance(nsISupports *aOuter, REFNSIID aIID, 
-                                  const char* aPluginMIMEType,
-                                  void **aResult);
+  NS_DECL_NSIFACTORY
+  NS_DECL_NSIPLUGIN
   
-  NS_IMETHOD Initialize(void);
-
-  NS_IMETHOD Shutdown(void);
-
-  NS_IMETHOD GetMIMEDescription(const char* *resultingDesc);
-
-  NS_IMETHOD GetValue(nsPluginVariable variable, void *value);
-
   ////////////////////////////////////////////////////////////////////
   // ns4xPlugin-specific methods
 
diff --git a/modules/plugin/base/src/ns4xPluginInstance.h b/modules/plugin/base/src/ns4xPluginInstance.h
index 319a445399aa..c8f86a969c22 100644
--- a/modules/plugin/base/src/ns4xPluginInstance.h
+++ b/modules/plugin/base/src/ns4xPluginInstance.h
@@ -90,42 +90,8 @@ class ns4xPluginInstance : public nsIPluginInstance,
 public:
 
     NS_DECL_ISUPPORTS
-
-    ////////////////////////////////////////////////////////////////////////
-    // nsIPluginInstance methods
-
-    /**
-     * Actually initialize the plugin instance. This calls the 4.x <b>newp</b>
-     * callback, and may return an error (which is why it is distinct from the
-     * constructor.) If an error is returned, the caller should <i>not</i>
-     * continue to use the <b>ns4xPluginInstance</b> object.
-     */
-    NS_METHOD Initialize(nsIPluginInstancePeer* peer);
-
-    NS_IMETHOD GetPeer(nsIPluginInstancePeer* *resultingPeer);
-
-    NS_IMETHOD Start(void);
-
-    NS_IMETHOD Stop(void);
-
-    NS_IMETHOD Destroy(void);
-
-    NS_IMETHOD SetWindow(nsPluginWindow* window);
-
-    NS_IMETHOD NewStream(nsIPluginStreamListener** listener);
-
-    NS_IMETHOD Print(nsPluginPrint* platformPrint);
-
-    NS_IMETHOD GetValue(nsPluginInstanceVariable variable, void *value);
-
-    NS_IMETHOD HandleEvent(nsPluginEvent* event, PRBool* handled);
-    
-    ////////////////////////////////////////////////////////////////////////
-    // nsIScriptablePlugin methods
-
-    NS_IMETHOD GetScriptablePeer(void * *aScriptablePeer);
-
-    NS_IMETHOD GetScriptableInterface(nsIID * *aScriptableInterface);
+    NS_DECL_NSIPLUGININSTANCE
+    NS_DECL_NSISCRIPTABLEPLUGIN
 
     ////////////////////////////////////////////////////////////////////////
     // nsIPluginInstanceInternal methods
diff --git a/modules/plugin/base/src/ns4xPluginStreamListener.h b/modules/plugin/base/src/ns4xPluginStreamListener.h
index 0081e3e98126..2ebef2062e5f 100644
--- a/modules/plugin/base/src/ns4xPluginStreamListener.h
+++ b/modules/plugin/base/src/ns4xPluginStreamListener.h
@@ -54,16 +54,7 @@ class ns4xPluginStreamListener : public nsIPluginStreamListener,
 {
 public:
   NS_DECL_ISUPPORTS
-
-  // from nsIPluginStreamListener:
-  NS_IMETHOD OnStartBinding(nsIPluginStreamInfo* pluginInfo);
-  NS_IMETHOD OnDataAvailable(nsIPluginStreamInfo* pluginInfo,
-                             nsIInputStream* input, PRUint32 length);
-  NS_IMETHOD OnFileAvailable( nsIPluginStreamInfo* pluginInfo,
-                              const char* fileName);
-  NS_IMETHOD OnStopBinding(nsIPluginStreamInfo* pluginInfo, nsresult status);
-  NS_IMETHOD GetStreamType(nsPluginStreamType *result);
-
+  NS_DECL_NSIPLUGINSTREAMLISTENER
   NS_DECL_NSITIMERCALLBACK
 
   // ns4xPluginStreamListener specific methods:
diff --git a/modules/plugin/base/src/nsPluginHostImpl.cpp b/modules/plugin/base/src/nsPluginHostImpl.cpp
index 243149ecb079..a9d3c62f012b 100644
--- a/modules/plugin/base/src/nsPluginHostImpl.cpp
+++ b/modules/plugin/base/src/nsPluginHostImpl.cpp
@@ -297,7 +297,9 @@ PRBool ReadSectionHeader(nsPluginManifestLineReader& reader, const char *token)
 class nsPluginDocReframeEvent: public nsRunnable {
 public:
   nsPluginDocReframeEvent(nsISupportsArray* aDocs) { mDocs = aDocs; }
-  NS_IMETHOD Run();
+
+  NS_DECL_NSIRUNNABLE
+
   nsCOMPtr<nsISupportsArray> mDocs;
 };
 
@@ -955,20 +957,23 @@ public:
   nsPluginUnloadEvent(PRLibrary* aLibrary)
     : mLibrary(aLibrary)
   {}
-
-  NS_IMETHOD Run() {
-    if (mLibrary) {
-      // put our unload call in a saftey wrapper
-      NS_TRY_SAFE_CALL_VOID(PR_UnloadLibrary(mLibrary), nsnull, nsnull);
-    } else {
-      NS_WARNING("missing library from nsPluginUnloadEvent");
-    }
-    return NS_OK;
-  }
-
+ 
+  NS_DECL_NSIRUNNABLE
+ 
   PRLibrary* mLibrary;
 };
 
+NS_IMETHODIMP nsPluginUnloadEvent::Run()
+{
+  if (mLibrary) {
+    // put our unload call in a saftey wrapper
+    NS_TRY_SAFE_CALL_VOID(PR_UnloadLibrary(mLibrary), nsnull, nsnull);
+  } else {
+    NS_WARNING("missing library from nsPluginUnloadEvent");
+  }
+  return NS_OK;
+}
+
 // unload plugin asynchronously if possible, otherwise just unload now
 nsresult PostPluginUnloadEvent(PRLibrary* aLibrary)
 {
@@ -1050,8 +1055,8 @@ public:
 
   NS_DECL_ISUPPORTS
 
-  // nsIPluginStreamInfo interface
-
+  // nsI4xPluginStreamInfo interface
+ 
   NS_IMETHOD
   GetContentType(nsMIMEType* result);
 
diff --git a/modules/plugin/base/src/nsPluginHostImpl.h b/modules/plugin/base/src/nsPluginHostImpl.h
index fe486a5b4fe0..4b6e55454b7f 100644
--- a/modules/plugin/base/src/nsPluginHostImpl.h
+++ b/modules/plugin/base/src/nsPluginHostImpl.h
@@ -64,6 +64,9 @@
 #include "nsIPrefBranch.h"
 #include "nsWeakReference.h"
 
+// XXX this file really doesn't think this is possible, but ...
+#include "nsIFactory.h"
+
 class ns4xPlugin;
 class nsIComponentManager;
 class nsIFile;
@@ -274,139 +277,18 @@ public:
 
   //nsIPluginHost interface - used to communicate to the nsPluginInstanceOwner
 
-  NS_IMETHOD
-  Init(void);
-
-  NS_IMETHOD
-  Destroy(void);
-
-  NS_IMETHOD
-  LoadPlugins(void);
-
-  NS_IMETHOD
-  GetPluginFactory(const char *aMimeType, nsIPlugin** aPlugin);
-
-
-  NS_IMETHOD
-  InstantiatePluginForChannel(nsIChannel* aChannel,
-                              nsIPluginInstanceOwner* aOwner,
-                              nsIStreamListener** aListener);
-
-  NS_IMETHOD
-  InstantiateEmbeddedPlugin(const char *aMimeType, nsIURI* aURL, nsIPluginInstanceOwner *aOwner);
-
-  NS_IMETHOD
-  InstantiateFullPagePlugin(const char *aMimeType, nsIURI* aURI, nsIStreamListener *&aStreamListener, nsIPluginInstanceOwner *aOwner);
-
-  NS_IMETHOD
-  SetUpPluginInstance(const char *aMimeType, nsIURI *aURL, nsIPluginInstanceOwner *aOwner);
-
-  NS_IMETHOD
-  IsPluginEnabledForType(const char* aMimeType);
-
-  NS_IMETHOD
-  IsPluginEnabledForExtension(const char* aExtension, const char* &aMimeType);
-
-  NS_IMETHOD
-  GetPluginCount(PRUint32* aPluginCount);
-  
-  NS_IMETHOD
-  GetPlugins(PRUint32 aPluginCount, nsIDOMPlugin** aPluginArray);
-
-  NS_IMETHOD
-  HandleBadPlugin(PRLibrary* aLibrary, nsIPluginInstance *instance);
-
-  //nsIPluginManager2 interface - secondary methods that nsIPlugin communicates to
-
-  NS_IMETHOD
-  BeginWaitCursor(void);
-
-  NS_IMETHOD
-  EndWaitCursor(void);
-
-  NS_IMETHOD
-  SupportsURLProtocol(const char* protocol, PRBool *result);
-
-  NS_IMETHOD
-  NotifyStatusChange(nsIPlugin* plugin, nsresult errorStatus);
-  
-  NS_IMETHOD
-  FindProxyForURL(const char* url, char* *result);
-
-  NS_IMETHOD
-  RegisterWindow(nsIEventHandler* handler, nsPluginPlatformWindowRef window);
-  
-  NS_IMETHOD
-  UnregisterWindow(nsIEventHandler* handler, nsPluginPlatformWindowRef window);
-
-  NS_IMETHOD
-  AllocateMenuID(nsIEventHandler* handler, PRBool isSubmenu, PRInt16 *result);
-
-  NS_IMETHOD
-  DeallocateMenuID(nsIEventHandler* handler, PRInt16 menuID);
-
-  NS_IMETHOD
-  HasAllocatedMenuID(nsIEventHandler* handler, PRInt16 menuID, PRBool *result);
+  NS_DECL_NSIPLUGINHOST
+  NS_DECL_NSIPLUGINMANAGER2
 
   NS_IMETHOD
   ProcessNextEvent(PRBool *bEventHandled);
 
-  // nsIFactory interface, from nsIPlugin.
   // XXX not currently used?
-  NS_IMETHOD CreateInstance(nsISupports *aOuter,
-                            REFNSIID aIID,
-                            void **aResult);
-
-  NS_IMETHOD LockFactory(PRBool aLock);
-
-  // nsIFileUtilities interface
-
-  NS_IMETHOD GetProgramPath(const char* *result);
-
-  NS_IMETHOD GetTempDirPath(const char* *result);
-
-  NS_IMETHOD NewTempFileName(const char* prefix, PRUint32 bufLen, char* resultBuf);
-
-  // nsICookieStorage interface
-
-  /**
-   * Retrieves a cookie from the browser's persistent cookie store.
-   * @param inCookieURL        URL string to look up cookie with.
-   * @param inOutCookieBuffer  buffer large enough to accomodate cookie data.
-   * @param inOutCookieSize    on input, size of the cookie buffer, on output cookie's size.
-   */
-  NS_IMETHOD
-  GetCookie(const char* inCookieURL, void* inOutCookieBuffer, PRUint32& inOutCookieSize);
-  
-  /**
-   * Stores a cookie in the browser's persistent cookie store.
-   * @param inCookieURL        URL string store cookie with.
-   * @param inCookieBuffer     buffer containing cookie data.
-   * @param inCookieSize       specifies  size of cookie data.
-   */
-  NS_IMETHOD
-  SetCookie(const char* inCookieURL, const void* inCookieBuffer, PRUint32 inCookieSize);
-  
-  // Methods from nsIObserver
-  NS_IMETHOD
-  Observe(nsISupports *aSubject, const char *aTopic, const PRUnichar *someData);
-
-  // Methods from nsPIPluginHost
-  NS_IMETHOD
-  SetIsScriptableInstance(nsIPluginInstance *aPluginInstance, PRBool aScriptable);
-
-  NS_IMETHOD
-  ParsePostBufferToFixHeaders(const char *inPostData, PRUint32 inPostDataLen, 
-              char **outPostData, PRUint32 *outPostDataLen);
-  
-  NS_IMETHOD
-  CreateTmpFileToPost(const char *postDataURL, char **pTmpFileName);
-
-  NS_IMETHOD
-  NewPluginNativeWindow(nsPluginNativeWindow ** aPluginNativeWindow);
-
-  NS_IMETHOD
-  DeletePluginNativeWindow(nsPluginNativeWindow * aPluginNativeWindow);
+  NS_DECL_NSIFACTORY
+  NS_DECL_NSIFILEUTILITIES
+  NS_DECL_NSICOOKIESTORAGE
+  NS_DECL_NSIOBSERVER
+  NS_DECL_NSPIPLUGINHOST
 
   /* Called by GetURL and PostURL */
 
@@ -428,9 +310,6 @@ public:
   AddHeadersToChannel(const char *aHeadersData, PRUint32 aHeadersDataLen, 
                       nsIChannel *aGenericChannel);
 
-  NS_IMETHOD
-  StopPluginInstance(nsIPluginInstance* aInstance);
-
   NS_IMETHOD
   AddUnusedLibrary(PRLibrary * aLibrary);
 
diff --git a/modules/plugin/base/src/nsPluginInstancePeer.h b/modules/plugin/base/src/nsPluginInstancePeer.h
index 7893e2326e91..b680729b5061 100644
--- a/modules/plugin/base/src/nsPluginInstancePeer.h
+++ b/modules/plugin/base/src/nsPluginInstancePeer.h
@@ -61,104 +61,13 @@ public:
   virtual ~nsPluginInstancePeerImpl();
 
   NS_DECL_ISUPPORTS
+  NS_DECL_NSIPLUGININSTANCEPEER
+  NS_DECL_NSIWINDOWLESSPLUGININSTANCEPEER
+  NS_DECL_NSIPLUGININSTANCEPEER2
+  NS_DECL_NSIPLUGINTAGINFO
+  NS_DECL_NSIPLUGINTAGINFO2
 
-  // nsIPluginInstancePeer interface
-
-  NS_IMETHOD
-  GetValue(nsPluginInstancePeerVariable variable, void *value);
-
-  NS_IMETHOD
-  GetMIMEType(nsMIMEType *result);
-
-  NS_IMETHOD
-  GetMode(nsPluginMode *result);
-
-  NS_IMETHOD
-  NewStream(nsMIMEType type, const char* target, nsIOutputStream* *result);
-
-  NS_IMETHOD
-  ShowStatus(const char* message);
-
-  NS_IMETHOD
-  SetWindowSize(PRUint32 width, PRUint32 height);
-
-  // nsIPluginInstancePeer2 interface
-
-  NS_IMETHOD
-  GetJSWindow(JSObject* *outJSWindow);
-  
-  NS_IMETHOD
-  GetJSThread(PRUint32 *outThreadID);
-
-  NS_IMETHOD
-  GetJSContext(JSContext* *outContext);
-
-  // nsIWindowlessPluginInstancePeer
-
-  // (Corresponds to NPN_InvalidateRect.)
-  NS_IMETHOD
-  InvalidateRect(nsPluginRect *invalidRect);
-
-  // (Corresponds to NPN_InvalidateRegion.)
-  NS_IMETHOD
-  InvalidateRegion(nsPluginRegion invalidRegion);
-
-  // (Corresponds to NPN_ForceRedraw.)
-  NS_IMETHOD
-  ForceRedraw(void);
-
-  /* The tag info interfaces all pass through calls to the 
-     nsPluginInstanceOwner (see nsObjectFrame.cpp) */
-
-  //nsIPluginTagInfo interface
-
-  NS_IMETHOD
-  GetAttributes(PRUint16& n, const char*const*& names, const char*const*& values);
-
-  NS_IMETHOD
-  GetAttribute(const char* name, const char* *result);
-
-  NS_IMETHOD
-  GetDOMElement(nsIDOMElement* *result);
-
-  //nsIPluginTagInfo2 interface
-
-  NS_IMETHOD
-  GetTagType(nsPluginTagType *result);
-
-  NS_IMETHOD
-  GetTagText(const char* *result);
-
-  NS_IMETHOD
-  GetParameters(PRUint16& n, const char*const*& names, const char*const*& values);
-
-  NS_IMETHOD
-  GetParameter(const char* name, const char* *result);
-  
-  NS_IMETHOD
-  GetDocumentBase(const char* *result);
-  
-  NS_IMETHOD
-  GetDocumentEncoding(const char* *result);
-  
-  NS_IMETHOD
-  GetAlignment(const char* *result);
-  
-  NS_IMETHOD
-  GetWidth(PRUint32 *result);
-  
-  NS_IMETHOD
-  GetHeight(PRUint32 *result);
-  
-  NS_IMETHOD
-  GetBorderVertSpace(PRUint32 *result);
-  
-  NS_IMETHOD
-  GetBorderHorizSpace(PRUint32 *result);
-
-  NS_IMETHOD
-  GetUniqueID(PRUint32 *result);
-
+  //XXX Why isn't this ifdef'd like the class declaration?
   //nsIJVMPluginTagInfo interface
 
   NS_IMETHOD
@@ -176,10 +85,7 @@ public:
   NS_IMETHOD
   GetMayScript(PRBool *result);
 
-  // nsPIPluginInstancePeer interface
-
-  NS_IMETHOD
-  GetOwner(nsIPluginInstanceOwner **aOwner);
+  NS_DECL_NSPIPLUGININSTANCEPEER
 
   //locals
 
diff --git a/modules/plugin/base/src/nsPluginNativeWindowOS2.cpp b/modules/plugin/base/src/nsPluginNativeWindowOS2.cpp
index abe63ed579c6..901878bbe5b4 100644
--- a/modules/plugin/base/src/nsPluginNativeWindowOS2.cpp
+++ b/modules/plugin/base/src/nsPluginNativeWindowOS2.cpp
@@ -77,8 +77,8 @@ public:
   MPARAM GetWParam() { return mWParam; };
   MPARAM GetLParam() { return mLParam; };
   PRBool InUse()     { return (mWnd!=NULL || mMsg!=0); };
-
-  NS_IMETHOD Run();
+  
+  NS_DECL_NSIRUNNABLE
 
 protected:
   PluginWindowWeakRef mPluginWindowRef;
diff --git a/modules/plugin/base/src/nsPluginNativeWindowWin.cpp b/modules/plugin/base/src/nsPluginNativeWindowWin.cpp
index 1108cb3000c0..c4d0a724dd3a 100644
--- a/modules/plugin/base/src/nsPluginNativeWindowWin.cpp
+++ b/modules/plugin/base/src/nsPluginNativeWindowWin.cpp
@@ -81,7 +81,7 @@ public:
   LPARAM GetLParam() { return mLParam; };
   PRBool InUse()     { return (mWnd!=NULL || mMsg!=0); };
 
-  NS_IMETHOD Run();
+  NS_DECL_NSIRUNNABLE
 
 protected:
   PluginWindowWeakRef mPluginWindowRef;
@@ -183,14 +183,19 @@ public:
   nsDelayedPopupsEnabledEvent(nsIPluginInstanceInternal *inst)
     : mInst(inst)
   {}
-  NS_IMETHOD Run() {
-    mInst->PushPopupsEnabledState(PR_FALSE);
-    return NS_OK;
-  }
+
+  NS_DECL_NSIRUNNABLE
+
 private:
   nsCOMPtr<nsIPluginInstanceInternal> mInst;
 };
 
+NS_IMETHODIMP nsDelayedPopupsEnabledEvent::Run()
+{
+  mInst->PushPopupsEnabledState(PR_FALSE);
+  return NS_OK;	
+}
+
 /**
  *   New plugin window procedure
  */