-dnl check for getopt in standard library
-AC_REPLACE_FUNCS([snprintf])
-AC_CHECK_FUNC([getopt_long], [], [AC_LIBOBJ([getopt])
- AC_LIBOBJ([getopt1])])
+AC_MSG_NOTICE([Checking requirements for IPv6 support...])
+enable_ipv6=true
+m4_define(NO_IPV6,[enable_ipv6=false])
+AC_CHECK_DECL(AF_INET6, [],[NO_IPV6],[#include <netinet/in.h>])
+AC_CHECK_FUNC(adns_addr2text, [],[NO_IPV6])
+if $enable_ipv6; then
+ AC_MSG_NOTICE([Enabling IPv6 support])
+ AC_DEFINE(CONFIG_IPV6, 1,
+ [Define to 1 to use IPv6 support in system and adns])
+else
+ AC_MSG_WARN([Disabling IPv6 support])
+fi