RFC 1918 address on open internet?

view story

http://serverfault.com – In trying to diagnose a failover problem with my Cisco ASA 5520 firewalls, I ran a traceroute to www.btfl.com and, much to my surprise, some of the hops came back as RFC 1918 addresses. Just to be clear, this host is not behind my firewall and there is no VPN involved. I have to connect across the open internet to get there. How/why is this possible? asa# traceroute www.btfl.com Tracing the route to 1 <redacted> 2 <redacted> 3 <redacted> 4 <redacted> 5 nap-edge-04.inet.qwest.net ( 0 msec 10 msec 10 msec 6 0 msec (HowTos)