We don't have an sa_len field.  Try to work around it.

--- fetchmail-5.6.0/ipv6-connect.c.salen	Mon Feb 12 16:28:50 2001
+++ fetchmail-5.6.0/ipv6-connect.c	Sat Apr  8 02:48:26 2000
@@ -21,7 +21,23 @@
 #include <signal.h>
 
 #ifndef SA_LEN
-#define SA_LEN(sa)	((sa)->sa_len)
+#define SA_LEN(sa)	xsa_len(sa)
+
+static size_t xsa_len(struct sockaddr *sa)
+{
+	switch(sa->sa_family) {
+#ifdef AF_INET
+		case AF_INET:
+			return sizeof(struct sockaddr_in);
+#endif
+#ifdef AF_INET6
+		case AF_INET6:
+			return sizeof(struct sockaddr_in6);
+#endif
+		default:
+			return sizeof(struct sockaddr);
+	}
+}
 #endif
 
 #ifdef INET6_ENABLE