diff --git a/reactos/include/basetsd.h b/reactos/include/basetsd.h
index 1e44712e2b4..83efaf64aca 100644
--- a/reactos/include/basetsd.h
+++ b/reactos/include/basetsd.h
@@ -63,7 +63,7 @@ typedef long LONG32, *PLONG32;
 #ifndef XFree86Server
 typedef int INT32, *PINT32;
 #endif /* ndef XFree86Server */
-typedef unsigned long ULONG32, *PULONG32;
+typedef unsigned int ULONG32, *PULONG32;
 typedef unsigned int DWORD32, *PDWORD32;
 typedef unsigned int UINT32, *PUINT32;
 
diff --git a/reactos/include/ntos/types.h b/reactos/include/ntos/types.h
index 1c296742ba0..f3a0973cc24 100644
--- a/reactos/include/ntos/types.h
+++ b/reactos/include/ntos/types.h
@@ -71,9 +71,9 @@ typedef short SHORT;
 
 typedef INT32 INT, *PINT;
 typedef LONG32 LONG, *PLONG;
-typedef ULONG32 DWORD, *PDWORD;
+typedef unsigned long DWORD, *PDWORD;
 typedef UINT32 UINT, *PUINT;
-typedef ULONG32 ULONG, *PULONG;
+typedef unsigned long ULONG, *PULONG;
 
 #ifndef _WCHAR_T_
 #define _WCHAR_T_
diff --git a/reactos/lib/rtl/mem.c b/reactos/lib/rtl/mem.c
index a50e43dc21f..6b9ace31886 100644
--- a/reactos/lib/rtl/mem.c
+++ b/reactos/lib/rtl/mem.c
@@ -1,5 +1,5 @@
 
-/* $Id: mem.c,v 1.3 2004/11/25 19:25:06 ekohl Exp $
+/* $Id$
  * 
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS kernel
@@ -39,7 +39,7 @@
  *
  * @implemented
  */
-ULONG STDCALL
+SIZE_T STDCALL
 RtlCompareMemory(IN const VOID *Source1,
                  IN const VOID *Source2,
                  IN SIZE_T Length)
diff --git a/reactos/ntoskrnl/mm/elf.c b/reactos/ntoskrnl/mm/elf.c
index 5dd5a0096f8..431aabb70a7 100644
--- a/reactos/ntoskrnl/mm/elf.c
+++ b/reactos/ntoskrnl/mm/elf.c
@@ -37,7 +37,7 @@ static __inline BOOLEAN Intsafe_CanAddULong32
 
 static __inline BOOLEAN Intsafe_AddULong32
 (
- OUT PULONG Result,
+ OUT PULONG32 Result,
  IN ULONG Addend1,
  IN ULONG Addend2
 )
@@ -83,7 +83,7 @@ static __inline BOOLEAN Intsafe_CanMulULong32
 
 static __inline BOOLEAN Intsafe_MulULong32
 (
- OUT PULONG Result,
+ OUT PULONG32 Result,
  IN ULONG Factor1,
  IN ULONG Factor2
 )
@@ -239,7 +239,7 @@ static __inline ULONG64 ElfFmtpSafeReadULong64
 )
 {
  PBYTE p;
- ULONG nSafeInput;
+ ULONG64 nSafeInput;
 
  RtlRetrieveUlonglong(&nSafeInput, Input);
 
@@ -257,7 +257,7 @@ static __inline ULONG64 ElfFmtpSafeReadULong64
 
 static __inline ULONG ElfFmtpSafeReadULong
 (
- IN CONST ULONG * Input,
+ IN CONST ULONG32 * Input,
  IN ULONG DataType
 )
 {
@@ -367,7 +367,7 @@ Elf64FmtCreateSection
  PMM_SECTION_SEGMENT pssSegments;
  Elf_Addr nImageBase = 0;
  Elf_Addr nEntryPoint;
- ULONG nPrevVirtualEndOfSegment;
+ ULONG32 nPrevVirtualEndOfSegment;
  ULONG i;
  ULONG j;