Had a scare in a data centre once when the UPS started trying to connect to an IP hosted somewhere in China. Turned out when it did a DNS lookup for the SNMP server (or something - sorry about hand-waviness) the first response it got back was an IPV6 address (DNS AAAA record). And since the crappy TCP stack on the device had no IPV6 support, it was just interpreting the first four bytes of the AAAA record as an IPV4 address. One of our super smart sysadmins worked out what was going on and tweaked the DNS to return A record first - problem solved.