--- wide-dhcpv6-20080615/prefixconf.c.orig	2013-05-14 22:26:46.433767395 +1000

+++ wide-dhcpv6-20080615/prefixconf.c	2013-05-14 23:17:49.229676947 +1000

@@ -451,6 +451,17 @@

 	ifpfx->paddr.sin6_len = sizeof(struct sockaddr_in6);

 #endif

 	ifpfx->paddr.sin6_addr = prefix->addr;

+

+	/* 

+         * dave (bevhost) thinks this should fix it rather than 

+         * generare the error below "invalid prefix length" 

+         * this way the sla-len can be left out of the config file 

+         * and calculated when the prefix is received

+         */

+	if (prefix->plen + pconf->ifid_len + pconf->sla_len > 128) {

+		pconf->sla_len = 128 - pconf->ifid_len - prefix->plen;

+	}

+

 	ifpfx->plen = prefix->plen + pconf->sla_len;

 	/*

 	 * XXX: our current implementation assumes ifid len is a multiple of 8