# define INVALID_SOCKET (-1)
# endif /* INVALID_SOCKET */
# endif
+
+/* Some IPv6 implementations are broken, disable them in known bad
+ * versions.
+ */
+# if !defined(OPENSSL_USE_IPV6)
+# if defined(AF_INET6) && !defined(OPENSSL_SYS_BEOS_BONE) && !defined(NETWARE_CLIB)
+# define OPENSSL_USE_IPV6 1
+# else
+# define OPENSSL_USE_IPV6 0
+# endif
+# endif
+
#endif
#if defined(__ultrix)