diff --git a/reactos/include/ddk/rtl.h b/reactos/include/ddk/rtl.h
index 48b4713079f..87e4e5f2b0e 100644
--- a/reactos/include/ddk/rtl.h
+++ b/reactos/include/ddk/rtl.h
@@ -1,13 +1,17 @@
-/* $Id: rtl.h,v 1.53 2001/06/22 12:39:48 ekohl Exp $
+/* $Id: rtl.h,v 1.54 2001/06/25 12:31:00 ekohl Exp $
  * 
  */
 
 #ifndef __DDK_RTL_H
 #define __DDK_RTL_H
 
+#if defined(__NTOSKRNL__) || defined(__NTDRIVER__) || defined(__NTHAL__) || defined(__NTDLL__) || defined (__NTAPP__)
+
 #include <stddef.h>
 #include <stdarg.h>
 
+#endif /* __NTOSKRNL__ || __NTDRIVER__ || __NTHAL__ || __NTDLL__ || __NTAPP__ */
+
 #include <pe.h>
 
 typedef struct _INITIAL_TEB
@@ -2077,6 +2081,8 @@ VOID STDCALL RtlMapGenericMask (PACCESS_MASK AccessMask, PGENERIC_MAPPING Generi
 
 /*  functions exported from NTOSKRNL.EXE which are considered RTL  */
 
+#if defined(__NTOSKRNL__) || defined(__NTDRIVER__) || defined(__NTHAL__) || defined(__NTDLL__) || defined(__NTAPP__)
+
 char *_itoa (int value, char *string, int radix);
 int _snprintf(char * buf, size_t cnt, const char *fmt, ...);
 int _snwprintf(wchar_t *buf, size_t cnt, const wchar_t *fmt, ...);
@@ -2149,4 +2155,6 @@ wchar_t *wcsstr(const wchar_t *s,const wchar_t *b);
 size_t wcstombs (char *mbstr, const wchar_t *wcstr, size_t count);
 int wctomb (char *mbchar, wchar_t wchar);
 
+#endif /* __NTOSKRNL__ || __NTDRIVER__ || __NTHAL__ || __NTDLL__ || __NTAPP__ */
+
 #endif /* __DDK_RTL_H */
diff --git a/reactos/include/ntos/types.h b/reactos/include/ntos/types.h
index b87b2df6f28..a703e1b4c2a 100644
--- a/reactos/include/ntos/types.h
+++ b/reactos/include/ntos/types.h
@@ -117,6 +117,14 @@ typedef char CCHAR;
 #define FALSE 0
 #define TRUE 1
 
+#ifndef NULL
+#ifdef __cplusplus
+#define NULL 0
+#else
+#define NULL ((void*)0)
+#endif /* __cplusplus */
+#endif /* NULL */
+
 typedef const unsigned short *PCWSTR;
 
 typedef char* PCSZ;
diff --git a/reactos/lib/secur32/lsa.c b/reactos/lib/secur32/lsa.c
index 2a3cd5f4315..3c59510687c 100644
--- a/reactos/lib/secur32/lsa.c
+++ b/reactos/lib/secur32/lsa.c
@@ -1,4 +1,4 @@
-/* $Id: lsa.c,v 1.1 2000/08/12 19:33:19 dwelch Exp $
+/* $Id: lsa.c,v 1.2 2001/06/25 12:32:56 ekohl Exp $
  *
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS system libraries
@@ -14,6 +14,7 @@
 #include <ddk/ntddk.h>
 #include <napi/lpc.h>
 #include <lsass/lsass.h>
+#include <string.h>
 
 /* GLOBALS *******************************************************************/
 
diff --git a/reactos/subsys/csrss/makefile b/reactos/subsys/csrss/makefile
index 9d3e6d7d7c0..81c229ab272 100644
--- a/reactos/subsys/csrss/makefile
+++ b/reactos/subsys/csrss/makefile
@@ -1,4 +1,4 @@
-# $Id: makefile,v 1.12 2001/03/25 02:34:30 dwelch Exp $
+# $Id: makefile,v 1.13 2001/06/25 12:32:27 ekohl Exp $
 #
 # CSRSS: Client/server runtime subsystem
 #
@@ -8,7 +8,7 @@ PATH_TO_TOP = ../..
 
 TARGET=csrss
 
-CFLAGS = -I.
+CFLAGS = -D__NTAPP__ -I.
 
 OBJECTS_API = api/process.o api/wapi.o api/conio.o api/handle.o
 
diff --git a/reactos/subsys/smss/makefile b/reactos/subsys/smss/makefile
index 1d20ad0c704..b48789b738c 100644
--- a/reactos/subsys/smss/makefile
+++ b/reactos/subsys/smss/makefile
@@ -1,4 +1,4 @@
-# $Id: makefile,v 1.6 2000/11/20 19:59:14 ekohl Exp $
+# $Id: makefile,v 1.7 2001/06/25 12:32:39 ekohl Exp $
 #
 # Session Manager
 #
@@ -8,7 +8,7 @@ PATH_TO_TOP = ../..
 
 TARGET=smss
 
-BASE_CFLAGS = -I../../include
+CFLAGS = -D__NTAPP__
 
 OBJECTS = $(TARGET).o init.o smapi.o $(TARGET).coff