diff --git a/msvc/Makefile b/msvc/Makefile
index 5309309a8..a40d7bc10 100644
--- a/msvc/Makefile
+++ b/msvc/Makefile
@@ -10,7 +10,7 @@ srcdir	= ..\src
 
 SHORT_SITE_NAME   =
 LONG_SITE_NAME    =
-ECL_VERSION       = 0.9g
+ECL_VERSION       = 0.9h
 ARCHITECTURE      = PENTIUM4
 MACHINE_INSTANCE  = localhost
 MACHINE           =
@@ -29,6 +29,9 @@ GMP_TYPE      = gc
 # Set it to non-empty to include Win32 thread support
 ECL_THREADS   =
 
+# Set it to non-empty to enable Win32 debug support
+ECL_DEBUG   = 1
+
 # Add the extensions to include in the build process. Comment any
 # of the following lines to remove a feature from the build process
 # LISP->C compiled
@@ -49,9 +52,10 @@ TAR_DIR = %%CD%%\ecl-$(ECL_VERSION)
 #
 
 CC	= cl
-CFLAGS  = /MD /DGC_NOT_DLL
+CFLAGS  = -MD -DGC_NOT_DLL -nologo
 LIBS	= eclgc.lib eclgmp.lib user32.lib ws2_32.lib
-LDFLAGS	= -MD -Zi
+LDFLAGS	= -MD
+SHARED_LDFLAGS = -LD
 RM	= del
 RMDIR   = rmdir /Q /S
 MKDIR   = mkdir
@@ -88,6 +92,14 @@ LIBRARIES     =
 TARGETS       = ecl2$(EXE)
 DEF           = ecl.def
 
+# Enable debug information
+#
+!if "$(ECL_DEBUG)" != ""
+CFLAGS = $(CFLAGS) -Zi
+LDFLAGS = $(LDFLAGS) -Zi
+SHARED_LDFLAGS = -LDd
+!endif
+
 # Additional configuration for thread support
 #
 !if "$(ECL_THREADS)" == ""
@@ -168,9 +180,9 @@ compile.lsp: bare.lsp $(srcdir)/compile.lsp.in Makefile
 	    "@ECL_CFLAGS@" "" \
 	    "@CPPFLAGS@" "" \
 	    "@LDRPATH@" "" \
-	    "@LDFLAGS@" "/MD /link /LIBPATH:~S" \
-	    "@SHARED_LDFLAGS@" "/LDd" \
-	    "@BUNDLE_LDFLAGS@" "/LDd" \
+	    "@LDFLAGS@" "$(LDFLAGS) /link /LIBPATH:~S" \
+	    "@SHARED_LDFLAGS@" "$(SHARED_LDFLAGS)" \
+	    "@BUNDLE_LDFLAGS@" "$(SHARED_LDFLAGS)" \
 	    "@CLIBS@" "user32.lib ws2_32.lib" \
 	    "@STATICLIBS@" "eclgmp.lib eclgc.lib" \
 	    "@LIBS@" "user32.lib ws2_32.lib" \
@@ -204,9 +216,9 @@ cmp/cmpcfg.lsp: $(srcdir)/cmp/cmpcfg.lsp.in Makefile
 	    "@ECL_CFLAGS@" "" \
 	    "@CPPFLAGS@" "" \
 	    "@LDRPATH@" "" \
-	    "@LDFLAGS@" "/MD /link /LIBPATH:~S" \
-	    "@SHARED_LDFLAGS@" "/LDd" \
-	    "@BUNDLE_LDFLAGS@" "/LDd" \
+	    "@LDFLAGS@" "$(LDFLAGS) /link /LIBPATH:~S" \
+	    "@SHARED_LDFLAGS@" "$(SHARED_LDFLAGS)" \
+	    "@BUNDLE_LDFLAGS@" "$(SHARED_LDFLAGS)" \
 	    "@CLIBS@" "user32.lib ws2_32.lib" \
 	    "@STATICLIBS@" "eclgmp.lib eclgc.lib" \
 	    "@OBJEXT@" "obj" \
@@ -220,7 +232,7 @@ ecl-config.bat: util\ecl-config.bat Makefile
 	c\cut "~A" "$(libdir:\=/)"\
 	    "~*" "" \
 	    "@ECL_CFLAGS@" "$(CFLAGS)" \
-	    "@LDFLAGS@" "" \
+	    "@LDFLAGS@" "$(LDFLAGS)" \
 	    "@CLIBS@" "" \
 	    "@libdir@" "$(libdir:\=/)" \
 	    "@includedir@" "$(libdir:\=/)/h" \
@@ -229,7 +241,7 @@ ecl-config.bat: util\ecl-config.bat Makefile
 
 eclmin.lib: eclgmp.lib eclgc.lib lsp/config.lsp
 	cd c
-	$(MAKE) "ECL_THREADS = $(ECL_THREADS)"
+	$(MAKE) "ECL_THREADS = $(ECL_THREADS)" "ECL_CFLAGS = $(CFLAGS)"
 	cd ..
 eclgc.lib:
 	cd gc
diff --git a/msvc/c/Makefile b/msvc/c/Makefile
index 82e9bd8c1..f4b76e607 100644
--- a/msvc/c/Makefile
+++ b/msvc/c/Makefile
@@ -16,7 +16,7 @@ THREADS_FLAGS=
 #
 TRUE_CC = cl
 CC	= cl
-CFLAGS	= -c -MD -Zi -I./ -I$(srcdir) -I$(HDIR) -I../h -I$(top_srcdir)/gc/include -DHAVE_ISATTY $(THREADS_FLAGS) -DGC_NOT_DLL
+CFLAGS	= -c $(ECL_CFLAGS) -I./ -I$(srcdir) -I$(HDIR) -I../h -I$(top_srcdir)/gc/include -DHAVE_ISATTY $(THREADS_FLAGS)
 #	  -Wall -W -Wfloat-equal -Wundef -Wendif-labels -Wpointer-arith -Wcast-align \
 #	  -Wwrite-strings -Wconversion -Wsign-compare -Wmissing-prototypes -Wredundant-decls \
 #	  -Wunreachable-code -Winline
diff --git a/src/cmp/cmpcfg.lsp.in b/src/cmp/cmpcfg.lsp.in
index 4b852d618..d4b0cf357 100644
--- a/src/cmp/cmpcfg.lsp.in
+++ b/src/cmp/cmpcfg.lsp.in
@@ -9,9 +9,9 @@
 (setq *cc-optimize* #-msvc "-O"
                     #+msvc "-O2")
 (setq *ld-format* #-msvc "~A -o ~S -L~S ~{~S ~} ~@?"
-                  #+msvc "~A -Zi -Fe~S~* ~{~S ~} ~@?")
+                  #+msvc "~A -Fe~S~* ~{~S ~} ~@?")
 (setq *cc-format* #-msvc "~A ~A ~:[~*~;~A~] \"-I~A/h\" -w -c \"~A\" -o \"~A\""
-                  #+msvc "~A ~A ~:[~*~;~A~] -I\"~A/h\" -Zi -w -nologo -c \"~A\" -Fo\"~A\"")
+                  #+msvc "~A ~A ~:[~*~;~A~] -I\"~A/h\" -w -c \"~A\" -Fo\"~A\"")
 #-dlopen
 (setq *ld-flags* "@LDRPATH@ @LDFLAGS@ -lecl @CORE_LIBS@ @LIBS@ @FASL_LIBS@")
 #+dlopen
diff --git a/src/compile.lsp.in b/src/compile.lsp.in
index ba0313ab4..27cf2f7ea 100644
--- a/src/compile.lsp.in
+++ b/src/compile.lsp.in
@@ -42,10 +42,10 @@
       #+msvc "@CFLAGS@ @ECL_CFLAGS@ -I\"@true_srcdir@\"/h -I\"@true_builddir@\"/h"
       c::*cc-format*
       #-msvc "~A ~A ~:[~*~;~A~] -I\"@true_builddir@\"/h~* -w -c ~S -o ~S"
-      #+msvc "~A ~A ~:[~*~;~A~] -I\"@true_builddir@\"/h~* -Zi -w -nologo -c ~S -Fo~S"
+      #+msvc "~A ~A ~:[~*~;~A~] -I\"@true_builddir@\"/h~* -w -c ~S -Fo~S"
       c::*ld-format*
       #-msvc "~A -o ~S -L\"@true_builddir@\"~* ~{~S ~} ~@?"
-      #+msvc "~A -Zi -Fe~S~* ~{~S ~} ~@?")
+      #+msvc "~A -Fe~S~* ~{~S ~} ~@?")
 #-:wants-dlopen 
 (setf c::*ld-flags*
       "@LDFLAGS@ @LDRPATH@ @LIBPREFIX@ecl.@LIBEXT@ @CORE_LIBS@ @LIBS@ @FASL_LIBS@")