This thread is a little chaotic.
First, the DNS problem: Try using your ISP's nameservers in /etc/resolv.conf. Failing that, use the opendns servers.
Second, are you making any sysctl tweaks to IP (or anything network related) on your FreeBSD installation?
Third, don't try pinging
www.sun.com - they're dropping icmp echo requests.
Finally, I don't see that you tried a normal traceroute from your FreeBSD box to
www.orange.fr.
I'm not convinced there is an actual problem here yet (apart from possible slow name resolution).