diff --git a/xpcom/base/Makefile.in b/xpcom/base/Makefile.in
index 37abd11bcce7..75cb359614ff 100644
--- a/xpcom/base/Makefile.in
+++ b/xpcom/base/Makefile.in
@@ -72,7 +72,7 @@ REQUIRES	+= boehm
 endif
 
 ifeq ($(OS_ARCH),Darwin)
-CPPSRCS		+= nsMacUtils.cpp
+CPPSRCS		+= nsMacUtilsImpl.cpp
 endif
 
 EXPORTS		= \
diff --git a/xpcom/base/nsMacUtils.cpp b/xpcom/base/nsMacUtilsImpl.cpp
similarity index 96%
rename from xpcom/base/nsMacUtils.cpp
rename to xpcom/base/nsMacUtilsImpl.cpp
index f2049b4be0d6..0a6c0f00aee6 100644
--- a/xpcom/base/nsMacUtils.cpp
+++ b/xpcom/base/nsMacUtilsImpl.cpp
@@ -35,19 +35,19 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#include "nsMacUtils.h"
+#include "nsMacUtilsImpl.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <mach-o/fat.h>
 
-NS_IMPL_ISUPPORTS1(nsMacUtils, nsIMacUtils)
+NS_IMPL_ISUPPORTS1(nsMacUtilsImpl, nsIMacUtils)
 
 /* readonly attribute boolean isUniversalBinary; */
 // True when the main executable is a fat file supporting at least
 // ppc and x86 (universal binary).
-NS_IMETHODIMP nsMacUtils::GetIsUniversalBinary(PRBool *aIsUniversalBinary)
+NS_IMETHODIMP nsMacUtilsImpl::GetIsUniversalBinary(PRBool *aIsUniversalBinary)
 {
   static PRBool sInitialized = PR_FALSE,
                 sIsUniversalBinary = PR_FALSE;
diff --git a/xpcom/base/nsMacUtils.h b/xpcom/base/nsMacUtilsImpl.h
similarity index 86%
rename from xpcom/base/nsMacUtils.h
rename to xpcom/base/nsMacUtilsImpl.h
index 050e2a8f3ae3..79b5cfb03b7c 100644
--- a/xpcom/base/nsMacUtils.h
+++ b/xpcom/base/nsMacUtilsImpl.h
@@ -35,28 +35,28 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#ifndef nsMacUtils_h___
-#define nsMacUtils_h___
+#ifndef nsMacUtilsImpl_h___
+#define nsMacUtilsImpl_h___
 
 #include "nsIMacUtils.h"
 
-class nsMacUtils : public nsIMacUtils
+class nsMacUtilsImpl : public nsIMacUtils
 {
 public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSIMACUTILS
 
-  nsMacUtils() {}
+  nsMacUtilsImpl() {}
 
 private:
-  ~nsMacUtils() {}
+  ~nsMacUtilsImpl() {}
 };
 
 // Global singleton service
 // 697BD3FD-43E5-41CE-AD5E-C339175C0818
-#define NS_MACUTILS_CLASSNAME "Mac OS X Utilities"
-#define NS_MACUTILS_CID \
+#define NS_MACUTILSIMPL_CLASSNAME "Mac OS X Utilities"
+#define NS_MACUTILSIMPL_CID \
  {0x697BD3FD, 0x43E5, 0x41CE, {0xAD, 0x5E, 0xC3, 0x39, 0x17, 0x5C, 0x08, 0x18}}
-#define NS_MACUTILS_CONTRACTID "@mozilla.org/xpcom/mac-utils;1"
+#define NS_MACUTILSIMPL_CONTRACTID "@mozilla.org/xpcom/mac-utils;1"
 
-#endif /* nsMacUtils_h___ */
+#endif /* nsMacUtilsImpl_h___ */
diff --git a/xpcom/build/nsXPComInit.cpp b/xpcom/build/nsXPComInit.cpp
index f6ff26c3e6e1..95adee42bfd1 100644
--- a/xpcom/build/nsXPComInit.cpp
+++ b/xpcom/build/nsXPComInit.cpp
@@ -131,7 +131,7 @@ NS_DECL_CLASSINFO(nsStringInputStream)
 #endif
 
 #ifdef XP_MACOSX
-#include "nsMacUtils.h"
+#include "nsMacUtilsImpl.h"
 #endif
 
 #include <locale.h>
@@ -222,7 +222,7 @@ NS_GENERIC_AGGREGATED_CONSTRUCTOR_INIT(nsProperties, Init)
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsUUIDGenerator)
 
 #ifdef XP_MACOSX
-NS_GENERIC_FACTORY_CONSTRUCTOR(nsMacUtils)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsMacUtilsImpl)
 #endif
 
 static NS_METHOD
@@ -419,7 +419,7 @@ static const nsModuleComponentInfo components[] = {
 #endif
 
 #ifdef XP_MACOSX
-    COMPONENT(MACUTILS, nsMacUtilsConstructor),
+    COMPONENT(MACUTILSIMPL, nsMacUtilsImplConstructor),
 #endif
 };