I see no mention of getaddressinfo in the POD for perl 5.10.1 at http://perldoc.perl.org/5.10.1/Socket.html. You can look at your installed version with:

perldoc Socket
perldoc -m Socket
[download]

However, perl 5.16 (currently on the web) Socket does mention it:

The entire getaddrinfo() subsystem can be exported using the tag :addrinfo ; this exports the getaddrinfo() and getnameinfo() functions