new file mode 100644
--- /dev/null
+++ b/m4/arpa_inet_h.m4
@@ -0,0 +1,18 @@
+# arpa_inet_h.m4 serial 1
+dnl Copyright (C) 2006 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by Simon Josefsson
+
+AC_DEFUN([gl_HEADER_ARPA_INET],
+[
+  AC_CHECK_HEADERS_ONCE([arpa/inet.h])
+  if test $ac_cv_header_arpa_inet_h = yes; then
+    ARPA_INET_H=''
+  else
+    ARPA_INET_H='arpa/inet.h'
+  fi
+  AC_SUBST(ARPA_INET_H)
+])

new file mode 100644
--- /dev/null
+++ b/modules/arpa_inet
@@ -0,0 +1,32 @@
+Description:
+A <arpa/inet.h> for systems lacking it (e.g., Mingw).
+
+Files:
+m4/arpa_inet_h.m4
+
+Depends-on:
+sys_socket
+
+configure.ac:
+gl_HEADER_ARPA_INET
+
+Makefile.am:
+BUILT_SOURCES += $(ARPA_INET_H)
+
+# We need the following in order to create <arpa/inet.h> when the system
+# doesn't have one.
+arpa/inet.h:
+	test -d arpa || mkdir arpa
+	echo '#include <sys/socket.h>' >$@-t
+	mv $@-t $@
+MOSTLYCLEANFILES += arpa/inet.h arpa/inet.h-t
+MOSTLYCLEANDIRS += arpa
+
+Include:
+#include <arpa/inet.h>
+
+License:
+LGPL
+
+Maintainer:
+Simon Josefsson