diff --git a/215.5/Makefile b/215.5/Makefile
index 648424f..73b5dce 100644
--- a/215.5/Makefile
+++ b/215.5/Makefile
@@ -11,6 +11,8 @@ SHELL = /bin/sh
 #
 FFLAGSSHARED = -fPIC
 CFLAGSSHARED = -fPIC
+FFLAGS = -fPIC
+CFLAGS = -fPIC
 #
 LDFLAGSSHARED = $(CXXFLAGS) -pthread -fPIC
 
diff --git a/215.5/Makeshared.subdir b/215.5/Makeshared.subdir
index f167145..0a8f232 100644
--- a/215.5/Makeshared.subdir
+++ b/215.5/Makeshared.subdir
@@ -42,7 +42,14 @@ objects += $(patsubst $(DIRNAME)/%.c,$(TMPDIR)/%.o,$(wildcard $(DIRNAME)/*.c))
 $(LIBNAME): $(objects)
 	@mkdir -p $(LIBDIR)
 	@echo creating the shared library $@
-	$(CXX) $(LDFLAGSSHARED) $(objects) -o $@ -shared -Wl,-soname,$(notdir $@)
+	case ${ARCH} in \
+	  Linux-*) \
+	    $(CXX) $(LDFLAGSSHARED) $(objects) -o $@ -shared -Wl,-soname,$(notdir $@) \
+	  ;;\
+	  Darwin-*) \
+	    $(CXX) $(LDFLAGSSHARED) $(objects) -Wl,-commons,use_dylibs -o $@ -shared -L$(dir $(shell gfortran --print-file-name=libgfortran.a)) $(FLIBS) -dynamic \
+	  ;; \
+	esac
 
 deps := $(patsubst $(DIRNAME)/%.F,$(TMPDIR)/%.d,$(wildcard $(DIRNAME)/*.F))
 
diff --git a/215.5/configure b/215.5/configure
index c8382cc..105950e 100755
--- a/215.5/configure
+++ b/215.5/configure
@@ -74,10 +74,6 @@ export CXXFLAGS_DBG="-g -ansi -pedantic -W -Wall"
 # Find platform.
 #
 export ARCH="`uname`"
-export theGcc=`g++ --version | head -n 1 | awk '{print$3}' | awk -F . '{print $1}'`
-if [ ${theGcc} = 4 ]; then
-  export ARCH=${ARCH}-gcc4
-fi
 echo Platform is $ARCH
 
 #default platform settings:
@@ -98,24 +94,6 @@ if [ ${COMPMODE} = DBG ]; then
   export CXXFLAGS="${CXXFLAGS_DBG}"
 fi
 if [ $ARCH = Linux ]; then
-  export FC=g77
-  export FFLAGS="${FFLAGS_OPT} -Wno-globals"
-  export CFLAGS="${CFLAGS_OPT}"
-  export CXXFLAGS="${CXXFLAGS_OPT}"
-  export FLIBS="-lfrtbegin -lg2c"
-  if [ ${COMPMODE} = OPT ]; then
-    export FFLAGS="${FFLAGS_OPT}"
-    export CFLAGS="${CFLAGS_OPT}"
-    export CXXFLAGS="${CXXFLAGS_OPT}"
-  fi
-  if [ ${COMPMODE} = DBG ]; then
-    export FFLAGS="${FFLAGS_DBG} -Wno-globals"
-    export CFLAGS="${CFLAGS_DBG}"
-    export CXXFLAGS="${CXXFLAGS_DBG}"
-  fi
-fi
-# Linux platform with gcc4: new Fortran90 compiler.
-if [ $ARCH = Linux-gcc4 ]; then
   export FC=gfortran
   export FFLAGS="${FFLAGS_OPT}"
   export CFLAGS="${CFLAGS_OPT}"