diff --git a/js/src/config/WINNT5.0.mk b/js/src/config/WINNT5.0.mk
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+++ b/js/src/config/WINNT5.0.mk
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+# -*- Mode: makefile -*-
+#
+# The contents of this file are subject to the Netscape Public
+# License Version 1.1 (the "License"); you may not use this file
+# except in compliance with the License. You may obtain a copy of
+# the License at http://www.mozilla.org/NPL/
+#
+# Software distributed under the License is distributed on an "AS
+# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express oqr
+# implied. See the License for the specific language governing
+# rights and limitations under the License.
+#
+# The Original Code is Mozilla Communicator client code, released
+# March 31, 1998.
+#
+# The Initial Developer of the Original Code is Netscape
+# Communications Corporation.  Portions created by Netscape are
+# Copyright (C) 1998 Netscape Communications Corporation. All
+# Rights Reserved.
+#
+# Contributor(s): 
+#
+# Alternatively, the contents of this file may be used under the
+# terms of the GNU Public License (the "GPL"), in which case the
+# provisions of the GPL are applicable instead of those above.
+# If you wish to allow use of your version of this file only
+# under the terms of the GPL and not to allow others to use your
+# version of this file under the NPL, indicate your decision by
+# deleting the provisions above and replace them with the notice
+# and other provisions required by the GPL.  If you do not delete
+# the provisions above, a recipient may use your version of this
+# file under either the NPL or the GPL.
+
+#
+# Config for Windows NT using MS Visual C++ (version?)
+#
+
+CC = cl
+
+RANLIB = echo
+
+#.c.o:
+#      $(CC) -c -MD $*.d $(CFLAGS) $<
+
+CPU_ARCH = x86 # XXX fixme
+GFX_ARCH = win32
+
+# MSVC compiler options for both debug/optimize
+# /nologo  - suppress copyright message
+# /W3      - Warning level 3
+# /Gm      - enable minimal rebuild
+# /Z7      - put debug info into the executable, not in .pdb file
+# /YX      - automatic precompiled headers
+# /GX      - enable C++ exception support
+WIN_CFLAGS = /nologo /W3 /Fp$(OBJDIR)/js.pch
+
+# MSVC compiler options for debug builds linked to MSVCRTD.DLL
+# /MDd     - link with MSVCRTD.LIB (Dynamically-linked, multi-threaded, debug C-runtime)
+# /Od      - minimal optimization
+WIN_IDG_CFLAGS = /MDd /Od /Z7 
+
+# MSVC compiler options for debug builds linked to MSVCRT.DLL
+# /MD      - link with MSVCRT.LIB (Dynamically-linked, multi-threaded, debug C-runtime)
+# /Od      - minimal optimization
+WIN_DEBUG_CFLAGS = /MD /Od /Z7 
+
+# MSVC compiler options for release (optimized) builds
+# /MD      - link with MSVCRT.LIB (Dynamically-linked, multi-threaded, C-runtime)
+# /O2      - Optimize for speed
+# /G5      - Optimize for Pentium
+WIN_OPT_CFLAGS = /MD /O2
+
+ifdef BUILD_OPT
+OPTIMIZER = $(WIN_OPT_CFLAGS)
+else
+ifdef BUILD_IDG
+OPTIMIZER = $(WIN_IDG_CFLAGS)
+else
+OPTIMIZER = $(WIN_DEBUG_CFLAGS)
+endif
+endif
+
+OS_CFLAGS = -DXP_PC -DWIN32 -D_WINDOWS -D_WIN32 $(WIN_CFLAGS)
+JSDLL_CFLAGS = -DEXPORT_JS_API
+OS_LIBS = -lm -lc
+
+PREBUILT_CPUCFG = 1
+USE_MSVC = 1
+
+LIB_LINK_FLAGS=kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib\
+ advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib oldnames.lib /nologo\
+ /subsystem:windows /dll /debug /pdb:none\
+ /machine:I386
+
+EXE_LINK_FLAGS=kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib\
+ advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib oldnames.lib /nologo\
+ /subsystem:console /debug /pdb:none\
+ /machine:I386
+
+# CAFEDIR = t:/cafe
+# JCLASSPATH = $(CAFEDIR)/Java/Lib/classes.zip
+# JAVAC = $(CAFEDIR)/Bin/sj.exe
+# JAVAH = $(CAFEDIR)/Java/Bin/javah.exe
+# JCFLAGS = -I$(CAFEDIR)/Java/Include -I$(CAFEDIR)/Java/Include/win32