diff --git a/content/base/src/nsDocument.cpp b/content/base/src/nsDocument.cpp
index 9e79f1eaa9d1..185bc533903f 100644
--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -80,6 +80,7 @@
 #include "nsIDOMRange.h"
 #include "nsIEnumerator.h"
 
+static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
 static NS_DEFINE_IID(kIDOMTextIID, NS_IDOMTEXT_IID);
 static NS_DEFINE_IID(kIDOMCommentIID, NS_IDOMCOMMENT_IID);
 static NS_DEFINE_IID(kIDocumentIID, NS_IDOCUMENT_IID);
@@ -219,7 +220,6 @@ nsDOMStyleSheetCollection::QueryInterface(REFNSIID aIID, void** aInstancePtrResu
     return NS_ERROR_NULL_POINTER;
   }
 
-  static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
   if (aIID.Equals(kIDOMStyleSheetCollectionIID)) {
     nsIDOMStyleSheetCollection *tmp = this;
     *aInstancePtrResult = (void*) tmp;
@@ -417,7 +417,6 @@ NS_IMPL_RELEASE(nsDOMImplementation)
 nsresult 
 nsDOMImplementation::QueryInterface(REFNSIID aIID, void** aInstancePtr)
 {
-  static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
   if (nsnull == aInstancePtr) {
     return NS_ERROR_NULL_POINTER;
   }
diff --git a/layout/base/src/nsDocument.cpp b/layout/base/src/nsDocument.cpp
index 9e79f1eaa9d1..185bc533903f 100644
--- a/layout/base/src/nsDocument.cpp
+++ b/layout/base/src/nsDocument.cpp
@@ -80,6 +80,7 @@
 #include "nsIDOMRange.h"
 #include "nsIEnumerator.h"
 
+static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
 static NS_DEFINE_IID(kIDOMTextIID, NS_IDOMTEXT_IID);
 static NS_DEFINE_IID(kIDOMCommentIID, NS_IDOMCOMMENT_IID);
 static NS_DEFINE_IID(kIDocumentIID, NS_IDOCUMENT_IID);
@@ -219,7 +220,6 @@ nsDOMStyleSheetCollection::QueryInterface(REFNSIID aIID, void** aInstancePtrResu
     return NS_ERROR_NULL_POINTER;
   }
 
-  static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
   if (aIID.Equals(kIDOMStyleSheetCollectionIID)) {
     nsIDOMStyleSheetCollection *tmp = this;
     *aInstancePtrResult = (void*) tmp;
@@ -417,7 +417,6 @@ NS_IMPL_RELEASE(nsDOMImplementation)
 nsresult 
 nsDOMImplementation::QueryInterface(REFNSIID aIID, void** aInstancePtr)
 {
-  static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
   if (nsnull == aInstancePtr) {
     return NS_ERROR_NULL_POINTER;
   }
diff --git a/network/module/nsNetStream.cpp b/network/module/nsNetStream.cpp
index a44cf9101f6c..26a0e6ae1b42 100644
--- a/network/module/nsNetStream.cpp
+++ b/network/module/nsNetStream.cpp
@@ -30,8 +30,8 @@ extern "C" {
 }
 
 
-NS_DEFINE_IID(kIInputStreamIID, NS_IINPUTSTREAM_IID);
-NS_DEFINE_IID(kIConnectionInfoIID, NS_ICONNECTIONINFO_IID);
+static NS_DEFINE_IID(kIInputStreamIID, NS_IINPUTSTREAM_IID);
+static NS_DEFINE_IID(kIConnectionInfoIID, NS_ICONNECTIONINFO_IID);
 
 #define BUFFER_BLOCK_SIZE   8192
 
@@ -146,7 +146,6 @@ nsresult nsNetlibStream::QueryInterface(const nsIID &aIID, void** aInstancePtr)
         return NS_ERROR_NULL_POINTER;
     }
     static NS_DEFINE_IID(kISupportsIID,     NS_ISUPPORTS_IID);
-    static NS_DEFINE_IID(kIInputStreamIID,  NS_IINPUTSTREAM_IID);
     static NS_DEFINE_IID(kIOutputStreamIID, NS_IOUTPUTSTREAM_IID);
     if (aIID.Equals(kIInputStreamIID)) {
         *aInstancePtr = (void*) ((nsIInputStream*)this);