diff --git a/scheme/last-revision b/scheme/last-revision
index 07f7d5f..8381dd2 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1309
+1311
diff --git a/src/Makefile.am b/src/Makefile.am
index 38facdb..2edb94e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -5,7 +5,7 @@ ikarus_SOURCES = ikarus-collect.c ikarus-exec.c ikarus-fasl.c \
   ikarus-flonums.c ikarus-main.c ikarus-numerics.c ikarus-print.c \
   ikarus-runtime.c ikarus-symbol-table.c ikarus-verify-integrity.c \
   ikarus-weak-pairs.c ikarus-winmmap.c ikarus-data.h \
-  ikarus-winmmap.h ikarus-enter.s cpu_has_sse2.s ikarus-io.c \
+  ikarus-winmmap.h ikarus-enter.S cpu_has_sse2.S ikarus-io.c \
   ikarus-process.c ikarus-getaddrinfo.h ikarus-getaddrinfo.c
 
 scheme_script_SOURCES = scheme-script.c
diff --git a/src/Makefile.in b/src/Makefile.in
index d7ff943..ad9005e 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -64,11 +64,12 @@ scheme_script_LDADD = $(LDADD)
 DEFAULT_INCLUDES = -I. -I$(top_builddir)@am__isrc@
 depcomp = $(SHELL) $(top_srcdir)/depcomp
 am__depfiles_maybe = depfiles
+CPPASCOMPILE = $(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \
+	$(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CCASFLAGS) $(CCASFLAGS)
 COMPILE = $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
 	$(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS)
 CCLD = $(CC)
 LINK = $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
-CCASCOMPILE = $(CCAS) $(AM_CCASFLAGS) $(CCASFLAGS)
 SOURCES = $(ikarus_SOURCES) $(nodist_ikarus_SOURCES) \
 	$(scheme_script_SOURCES)
 DIST_SOURCES = $(ikarus_SOURCES) $(scheme_script_SOURCES)
@@ -179,7 +180,7 @@ ikarus_SOURCES = ikarus-collect.c ikarus-exec.c ikarus-fasl.c \
   ikarus-flonums.c ikarus-main.c ikarus-numerics.c ikarus-print.c \
   ikarus-runtime.c ikarus-symbol-table.c ikarus-verify-integrity.c \
   ikarus-weak-pairs.c ikarus-winmmap.c ikarus-data.h \
-  ikarus-winmmap.h ikarus-enter.s cpu_has_sse2.s ikarus-io.c \
+  ikarus-winmmap.h ikarus-enter.S cpu_has_sse2.S ikarus-io.c \
   ikarus-process.c ikarus-getaddrinfo.h ikarus-getaddrinfo.c
 
 scheme_script_SOURCES = scheme-script.c
@@ -190,7 +191,7 @@ all: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) all-am
 
 .SUFFIXES:
-.SUFFIXES: .c .o .obj .s
+.SUFFIXES: .S .c .o .obj
 $(srcdir)/Makefile.in:  $(srcdir)/Makefile.am  $(am__configure_deps)
 	@for dep in $?; do \
 	  case '$(am__configure_deps)' in \
@@ -256,7 +257,9 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cpu_has_sse2.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-collect.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-enter.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-exec.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-fasl.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-flonums.Po@am__quote@
@@ -273,6 +276,20 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ikarus-winmmap.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/scheme-script.Po@am__quote@
 
+.S.o:
+@am__fastdepCCAS_TRUE@	$(CPPASCOMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
+@am__fastdepCCAS_TRUE@	mv -f $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(CPPASCOMPILE) -c -o $@ $<
+
+.S.obj:
+@am__fastdepCCAS_TRUE@	$(CPPASCOMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ `$(CYGPATH_W) '$<'`
+@am__fastdepCCAS_TRUE@	mv -f $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(CPPASCOMPILE) -c -o $@ `$(CYGPATH_W) '$<'`
+
 .c.o:
 @am__fastdepCC_TRUE@	$(COMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
 @am__fastdepCC_TRUE@	mv -f $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
@@ -287,12 +304,6 @@ distclean-compile:
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(COMPILE) -c `$(CYGPATH_W) '$<'`
 
-.s.o:
-	$(CCASCOMPILE) -c -o $@ $<
-
-.s.obj:
-	$(CCASCOMPILE) -c -o $@ `$(CYGPATH_W) '$<'`
-
 ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
 	list='$(SOURCES) $(HEADERS) $(LISP) $(TAGS_FILES)'; \
 	unique=`for i in $$list; do \
diff --git a/src/cpu_has_sse2.s b/src/cpu_has_sse2.S
similarity index 100%
rename from src/cpu_has_sse2.s
rename to src/cpu_has_sse2.S
diff --git a/src/ikarus-enter.s b/src/ikarus-enter.S
similarity index 100%
rename from src/ikarus-enter.s
rename to src/ikarus-enter.S