diff --git a/mozilla/intl/lwbrk/src/nsLWBreakerFImp.h b/mozilla/intl/lwbrk/src/nsLWBreakerFImp.h
index 7baeb87a45b..53682fdbee3 100644
--- a/mozilla/intl/lwbrk/src/nsLWBreakerFImp.h
+++ b/mozilla/intl/lwbrk/src/nsLWBreakerFImp.h
@@ -40,7 +40,7 @@
 
 
 
-#include "nsCom.h"
+#include "nscore.h"
 #include "nsISupports.h"
 
 #include "nsILineBreakerFactory.h"
diff --git a/mozilla/intl/unicharutil/src/nsCaseConversionImp2.h b/mozilla/intl/unicharutil/src/nsCaseConversionImp2.h
index 66b27aa4da8..1189010d4c0 100644
--- a/mozilla/intl/unicharutil/src/nsCaseConversionImp2.h
+++ b/mozilla/intl/unicharutil/src/nsCaseConversionImp2.h
@@ -39,7 +39,7 @@
 #ifndef nsCaseConversionImp2_h__
 #define nsCaseConversionImp2_h__
 
-#include "nsCom.h"
+#include "nscore.h"
 #include "nsISupports.h"
 
 #include "nsICaseConversion.h"
diff --git a/mozilla/intl/unicharutil/src/nsCategoryImp.cpp b/mozilla/intl/unicharutil/src/nsCategoryImp.cpp
index 7a44639fec9..b99eeb0c8e4 100644
--- a/mozilla/intl/unicharutil/src/nsCategoryImp.cpp
+++ b/mozilla/intl/unicharutil/src/nsCategoryImp.cpp
@@ -36,7 +36,7 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#include "nsCom.h"
+#include "nscore.h"
 #include "pratom.h"
 #include "nsUUDll.h"
 #include "nsISupports.h"
diff --git a/mozilla/intl/unicharutil/src/nsCategoryImp.h b/mozilla/intl/unicharutil/src/nsCategoryImp.h
index a4aaf6488e7..0edad6dd73c 100644
--- a/mozilla/intl/unicharutil/src/nsCategoryImp.h
+++ b/mozilla/intl/unicharutil/src/nsCategoryImp.h
@@ -38,7 +38,7 @@
 #ifndef nsCategoryImp_h__
 #define nsCategoryImp_h__
 
-#include "nsCom.h"
+#include "nscore.h"
 #include "nsISupports.h"
 #include "nsIUGenCategory.h"
 
diff --git a/mozilla/intl/unicharutil/src/nsUnicodeNormalizer.h b/mozilla/intl/unicharutil/src/nsUnicodeNormalizer.h
index a92783222c7..242f26e8e93 100644
--- a/mozilla/intl/unicharutil/src/nsUnicodeNormalizer.h
+++ b/mozilla/intl/unicharutil/src/nsUnicodeNormalizer.h
@@ -38,7 +38,7 @@
 #ifndef nsUnicodeNormalizer_h__
 #define nsUnicodeNormalizer_h__
 
-#include "nsCom.h"
+#include "nscore.h"
 #include "nsISupports.h"
 
 #include "nsIUnicodeNormalizer.h"
diff --git a/mozilla/mailnews/base/src/nsMessenger.h b/mozilla/mailnews/base/src/nsMessenger.h
index 8d4bf806a1b..b89921f5725 100644
--- a/mozilla/mailnews/base/src/nsMessenger.h
+++ b/mozilla/mailnews/base/src/nsMessenger.h
@@ -38,7 +38,6 @@
 #ifndef __nsMsgAppCore_h
 #define __nsMsgAppCore_h
 
-#include "nsCom.h"
 #include "nscore.h"
 #include "nsIMessenger.h"
 #include "nsCOMPtr.h"
diff --git a/mozilla/mailnews/base/util/nsMsgIncomingServer.cpp b/mozilla/mailnews/base/util/nsMsgIncomingServer.cpp
index cc786d51521..45416517de5 100644
--- a/mozilla/mailnews/base/util/nsMsgIncomingServer.cpp
+++ b/mozilla/mailnews/base/util/nsMsgIncomingServer.cpp
@@ -38,7 +38,6 @@
 
 #include "nsMsgIncomingServer.h"
 #include "nscore.h"
-#include "nsCom.h"
 #include "plstr.h"
 #include "prmem.h"
 #include "prprf.h"
diff --git a/mozilla/modules/oji/src/nsJVMManager.h b/mozilla/modules/oji/src/nsJVMManager.h
index b30b82d1856..24c24fb860b 100644
--- a/mozilla/modules/oji/src/nsJVMManager.h
+++ b/mozilla/modules/oji/src/nsJVMManager.h
@@ -40,7 +40,7 @@
 
 #include "jvmmgr.h"
 #include "prtypes.h"
-#include "nsCom.h"
+#include "nscore.h"
 #include "jni.h"
 #include "jsdbgapi.h"
 #include "nsError.h"
diff --git a/mozilla/uriloader/base/nsDocLoader.cpp b/mozilla/uriloader/base/nsDocLoader.cpp
index b23c9730e35..20ea848c25d 100644
--- a/mozilla/uriloader/base/nsDocLoader.cpp
+++ b/mozilla/uriloader/base/nsDocLoader.cpp
@@ -48,7 +48,7 @@
 
 #include "nsIURL.h"
 #include "nsCOMPtr.h"
-#include "nsCom.h"
+#include "nscore.h"
 #include "nsWeakPtr.h"
 
 #include "nsIDOMWindow.h"
diff --git a/mozilla/uriloader/exthandler/mac/nsDecodeAppleFile.h b/mozilla/uriloader/exthandler/mac/nsDecodeAppleFile.h
index ca030186432..0c2ad18bcb3 100644
--- a/mozilla/uriloader/exthandler/mac/nsDecodeAppleFile.h
+++ b/mozilla/uriloader/exthandler/mac/nsDecodeAppleFile.h
@@ -38,7 +38,6 @@
 #ifndef nsDecodeAppleFile_h__
 #define nsDecodeAppleFile_h__
 
-#include "nsCom.h"
 #include "nscore.h"
 #include "nsCOMPtr.h"
 #include "nsIFile.h"
diff --git a/mozilla/xpcom/ds/nsFixedSizeAllocator.h b/mozilla/xpcom/ds/nsFixedSizeAllocator.h
index 76c7324e354..507c191099a 100644
--- a/mozilla/xpcom/ds/nsFixedSizeAllocator.h
+++ b/mozilla/xpcom/ds/nsFixedSizeAllocator.h
@@ -129,7 +129,6 @@
 #define nsFixedSizeAllocator_h__
 
 #include "nscore.h"
-#include "nsCom.h"
 #include "nsError.h"
 #include "plarena.h"
 
diff --git a/mozilla/xpcom/ds/nsHashtable.h b/mozilla/xpcom/ds/nsHashtable.h
index 27353be386d..db627f4f037 100644
--- a/mozilla/xpcom/ds/nsHashtable.h
+++ b/mozilla/xpcom/ds/nsHashtable.h
@@ -40,7 +40,6 @@
 #include "pldhash.h"
 #include "prlock.h"
 #include "nscore.h"
-#include "nsCom.h"
 #include "nsString.h"
 
 class nsIObjectInputStream;
diff --git a/mozilla/xpcom/ds/nsStatistics.h b/mozilla/xpcom/ds/nsStatistics.h
index fe9e81dfbb4..40e834b76ed 100644
--- a/mozilla/xpcom/ds/nsStatistics.h
+++ b/mozilla/xpcom/ds/nsStatistics.h
@@ -29,7 +29,6 @@
 
 #include <stdio.h>
 #include "nscore.h"
-#include "nsCom.h"
 #include "plhash.h"
 
 /**
diff --git a/mozilla/xpcom/ds/nsVector.h b/mozilla/xpcom/ds/nsVector.h
index 2e5bd34814a..2ada43afd07 100644
--- a/mozilla/xpcom/ds/nsVector.h
+++ b/mozilla/xpcom/ds/nsVector.h
@@ -39,7 +39,7 @@
 #define nsVector_h__
 
 #include "plvector.h"
-#include "nsCom.h"
+#include "nscore.h"
 
 class nsVector : public PLVector {
 public:
diff --git a/mozilla/xpcom/glue/nsTraceRefcnt.h b/mozilla/xpcom/glue/nsTraceRefcnt.h
index d332f5172d0..38d9863ff0d 100644
--- a/mozilla/xpcom/glue/nsTraceRefcnt.h
+++ b/mozilla/xpcom/glue/nsTraceRefcnt.h
@@ -38,9 +38,8 @@
 #ifndef nsTraceRefcnt_h___
 #define nsTraceRefcnt_h___
 
-#include "nsCom.h"
-
-#include <stdio.h>
+#include "nscore.h"
+#include <stdio.h> // XXXldb We should remove this and add it where needed.
 
 class nsISupports;
 
diff --git a/mozilla/xpcom/tests/TestAutoPtr.cpp b/mozilla/xpcom/tests/TestAutoPtr.cpp
index cf23de594fc..cff0f864883 100644
--- a/mozilla/xpcom/tests/TestAutoPtr.cpp
+++ b/mozilla/xpcom/tests/TestAutoPtr.cpp
@@ -23,7 +23,7 @@
 
 #include "nsAutoPtr.h"
 #include <stdio.h>
-#include "nsCom.h"
+#include "nscore.h"
 
 class TestObjectBaseA {
     public: