diff --git a/extensions/pics/public/nsPICSElementObserver.h b/extensions/pics/public/nsPICSElementObserver.h
index 78e51c83b99..9097b631b4d 100644
--- a/extensions/pics/public/nsPICSElementObserver.h
+++ b/extensions/pics/public/nsPICSElementObserver.h
@@ -57,7 +57,7 @@ public:
                     PRUint32 numOfAttributes, const PRUnichar* nameArray[], 
                     const PRUnichar* valueArray[]);
 
-  NS_DECL_IOBSERVER
+  NS_DECL_NSIOBSERVER
 
   NS_DECL_ISUPPORTS
 
diff --git a/extensions/wallet/src/nsWalletService.h b/extensions/wallet/src/nsWalletService.h
index f169bd49a52..e2a64521b90 100644
--- a/extensions/wallet/src/nsWalletService.h
+++ b/extensions/wallet/src/nsWalletService.h
@@ -57,7 +57,7 @@ public:
   NS_IMETHOD SI_SignonViewerReturn(nsAutoString results);
 
   // nsIObserver
-  NS_DECL_IOBSERVER
+  NS_DECL_NSIOBSERVER
   NS_IMETHOD Notify(nsIContent* formNode);
 
   // nsIDocumentLoaderObserver
diff --git a/intl/chardet/src/nsMetaCharsetObserver.cpp b/intl/chardet/src/nsMetaCharsetObserver.cpp
index c7214de4149..8e195c5412a 100644
--- a/intl/chardet/src/nsMetaCharsetObserver.cpp
+++ b/intl/chardet/src/nsMetaCharsetObserver.cpp
@@ -68,7 +68,7 @@ public:
                     const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
 
   /* methode for nsIObserver */
-  NS_DECL_IOBSERVER
+  NS_DECL_NSIOBSERVER
 
   /* methode for nsIMetaCharsetService */
   NS_IMETHOD Start();
diff --git a/intl/chardet/src/nsXMLEncodingObserver.cpp b/intl/chardet/src/nsXMLEncodingObserver.cpp
index 0bc63d596ac..ce61eef6817 100644
--- a/intl/chardet/src/nsXMLEncodingObserver.cpp
+++ b/intl/chardet/src/nsXMLEncodingObserver.cpp
@@ -68,7 +68,7 @@ public:
                     const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
 
   /* methode for nsIObserver */
-  NS_DECL_IOBSERVER
+  NS_DECL_NSIOBSERVER
 
   /* methode for nsIXMLEncodingService */
   NS_IMETHOD Start();
diff --git a/xpcom/ds/nsIObserver.idl b/xpcom/ds/nsIObserver.idl
index 2c5314beb77..498639818e2 100644
--- a/xpcom/ds/nsIObserver.idl
+++ b/xpcom/ds/nsIObserver.idl
@@ -41,7 +41,4 @@ interface nsIObserver : nsISupports {
 
 #define NS_OBSERVER_CLASSNAME "Observer"
 
-#define NS_DECL_IOBSERVER \
-    NS_IMETHOD Observe( nsISupports*, const PRUnichar*, const PRUnichar* );
-
 %}
diff --git a/xpcom/ds/nsIObserverService.idl b/xpcom/ds/nsIObserverService.idl
index 9873a6863f7..e2a3e70a4aa 100644
--- a/xpcom/ds/nsIObserverService.idl
+++ b/xpcom/ds/nsIObserverService.idl
@@ -38,10 +38,4 @@ interface nsIObserverService : nsISupports {
 
 #define NS_OBSERVERSERVICE_CLASSNAME "Observer Service"
 
-#define NS_DECL_IOBSERVERSERVICE \
-  NS_IMETHOD AddObserver(nsIObserver*, const PRUnichar*);              \
-  NS_IMETHOD RemoveObserver(nsIObserver*, const PRUnichar*);           \
-  NS_IMETHOD EnumerateObserverList(const PRUnichar*, nsIEnumerator**); \
-  NS_IMETHOD Notify(nsISupports*, const PRUnichar*, const PRUnichar*); \
-
 %}
diff --git a/xpcom/ds/nsObserver.h b/xpcom/ds/nsObserver.h
index c7dbc623d12..b89b955ea45 100644
--- a/xpcom/ds/nsObserver.h
+++ b/xpcom/ds/nsObserver.h
@@ -31,7 +31,7 @@ public:
 
     NS_DEFINE_STATIC_CID_ACCESSOR( NS_OBSERVER_CID )
  
-    NS_DECL_IOBSERVER
+    NS_DECL_NSIOBSERVER
  
     nsObserver(nsISupports* outer);
     virtual ~nsObserver(void);
diff --git a/xpcom/ds/nsObserverService.h b/xpcom/ds/nsObserverService.h
index fd8842bce2d..572d9fcb26a 100644
--- a/xpcom/ds/nsObserverService.h
+++ b/xpcom/ds/nsObserverService.h
@@ -35,7 +35,7 @@ public:
 
 	static nsresult GetObserverService(nsIObserverService** anObserverService);
     
-    NS_DECL_IOBSERVERSERVICE
+    NS_DECL_NSIOBSERVERSERVICE
    
   nsObserverService();
   virtual ~nsObserverService(void);
diff --git a/xpcom/tests/TestObserverService.cpp b/xpcom/tests/TestObserverService.cpp
index f42379023a7..0fdc6d0c245 100644
--- a/xpcom/tests/TestObserverService.cpp
+++ b/xpcom/tests/TestObserverService.cpp
@@ -51,7 +51,7 @@ public:
     }
     virtual ~TestObserver() {}
     NS_DECL_ISUPPORTS
-    NS_DECL_IOBSERVER
+    NS_DECL_NSIOBSERVER
     nsString mName;
 };
 
diff --git a/xpfe/AppCores/src/nsBrowserAppCore.h b/xpfe/AppCores/src/nsBrowserAppCore.h
index efdbc4d0f90..464bc1f035b 100644
--- a/xpfe/AppCores/src/nsBrowserAppCore.h
+++ b/xpfe/AppCores/src/nsBrowserAppCore.h
@@ -128,7 +128,7 @@ class nsBrowserAppCore : public nsBaseAppCore,
 
 
     // nsIObserver
-    NS_DECL_IOBSERVER
+    NS_DECL_NSIOBSERVER
 
 
 	// nsISessionHistory methods