Index: configure.in
===================================================================
--- configure.in.orig	2009-09-25 20:34:39.000000000 +0200
+++ configure.in	2009-10-13 00:29:22.000000000 +0200
@@ -297,6 +297,44 @@ Linux)
 	;;
 esac
 
+dnl ************************************************************
+dnl Enable hiding of internal symbols in library to reduce its size and
+dnl speed dynamic linking of applications.  This currently is only supported
+dnl on gcc >= 4.0 and SunPro C.
+dnl
+AC_MSG_CHECKING([whether to enable hidden symbols in the library])
+AC_ARG_ENABLE(hidden-symbols,
+AC_HELP_STRING([--enable-hidden-symbols],[Hide internal symbols in library])
+AC_HELP_STRING([--disable-hidden-symbols],[Leave all symbols with default visibility in library]),
+[ case "$enableval" in
+  no)
+       AC_MSG_RESULT(no)
+       ;;
+  *)
+       AC_MSG_CHECKING([whether $CC supports it])
+       if test "$GCC" = yes ; then
+         if $CC --help --verbose 2>&1 | grep fvisibility= > /dev/null ; then
+           AC_MSG_RESULT(yes)
+           AC_DEFINE(M_EXPORT, [__attribute__ ((visibility ("default")))], [to make a symbol visible])
+           CFLAGS="$CFLAGS -fvisibility=hidden"
+         else
+            AC_MSG_RESULT(no)
+          fi
+
+       else
+         dnl Test for SunPro cc
+         if $CC 2>&1 | grep flags >/dev/null && $CC -flags | grep xldscope= >/dev/null ; then
+           AC_MSG_RESULT(yes)
+           AC_DEFINE(M_EXPORT, [__global], [to make a symbol visible])
+           CFLAGS="$CFLAGS -xldscope=hidden"
+         else
+           AC_MSG_RESULT(no)
+         fi
+       fi
+       ;;
+  esac ],
+       AC_MSG_RESULT(no)
+)
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT
 
Index: monetra.h
===================================================================
--- monetra.h.orig	2009-02-12 17:37:49.000000000 +0100
+++ monetra.h	2009-10-13 00:28:06.000000000 +0200
@@ -55,10 +55,14 @@ OF THE POSSIBILITY OF SUCH DAMAGE.
 #  else
 #    define M_SPEC __cdecl
 #  endif
-#else /* !WIN32 */
+#endif /* !WIN32 */
+
+#ifndef M_EXPORT
 #  define M_EXPORT
+#endif
+#ifndef M_SPEC
 #  define M_SPEC
-#endif /* !WIN32 */
+#endif
 
 #ifdef __cplusplus
 extern "C" {