--- configure.ac

+++ configure.ac

@@ -45,7 +45,12 @@

 AC_CHECK_FUNCS(getopt_long)

 AC_CHECK_FUNCS(getaddrinfo)

-AM_PATH_LIBGNUTLS(,AC_DEFINE(HAVE_GNUTLS,,"Use libgnutls"))

+AC_ARG_WITH([gnutls],

+            [AS_HELP_STRING([--with-gnutls],

+                            [Enable use of GnuTLS])])

+if test "$with_gnutls" != "no"; then

+  PKG_CHECK_MODULES(LIBGNUTLS, gnutls, AC_DEFINE(HAVE_GNUTLS,,"Use libgnutls"))

+fi

 dnl Check -Wall flag of GCC

 if test "x$GCC" = "xyes"; then