gethostbyaddr() or equivalent?

I have a table which contains IP addresses (written as a log by
applications which may or may not be local to the box hosting the
database):

log_time  | timestamp
ip_addr   | text

I would like to display the ip_addr column as a symbolic hostname (all
the IP addresses are local and well-known).  My initial attempt was to
write a simple PLPerl function:

CREATE FUNCTION fn_ip2name(text) returns text as '
use Socket;
return scalar gethostbyaddr(inet_aton($_[0]),AF_INET)
' language 'plperl';

However, this fails:

ERROR:  creation of function failed:
require trapped by operation mask at (eval 2) line 2.

Any suggestions?

--
Jeff Boes                                      vox 269.226.9550 ext 24
Database Engineer                                     fax 269.349.9076
Nexcerpt, Inc.                                 http://www.nexcerpt.com
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