--- a/common/discover.c~	2008-09-09 22:29:01.326643118 +0200
+++ a/common/discover.c	2008-09-09 22:34:07.565778860 +0200
@@ -421,6 +421,7 @@ begin_iface_scan(struct iface_conf_list 
 	}
 
 #ifdef DHCPv6
+	if (local_family == AF_INET6) {
 	ifaces->fp6 = fopen("/proc/net/if_inet6", "r");
 	if (ifaces->fp6 == NULL) {
 		log_error("Error opening '/proc/net/if_inet6' to "
@@ -431,6 +432,7 @@ begin_iface_scan(struct iface_conf_list 
 		ifaces->fp = NULL;
 		return 0;
 	}
+	}
 #endif
 
 	return 1;
@@ -700,9 +700,11 @@ next_iface(struct iface_info *info, int 
 		return 1;
 	}
 #ifdef DHCPv6
+	if (local_family == AF_INET6) {
 	if (!(*err)) {
 		return next_iface6(info, err, ifaces);
 	}
+	}
 #endif
 	return 0;
 }
@@ -719,7 +719,8 @@ end_iface_scan(struct iface_conf_list *i
 	close(ifaces->sock);
 	ifaces->sock = -1;
 #ifdef DHCPv6
-	fclose(ifaces->fp6);
+	if (local_family == AF_INET6)
+		fclose(ifaces->fp6);
 	ifaces->fp6 = NULL;
 #endif
 }