Or you can just use wget:

    #!/usr/bin/perl
    $status = `wget -O - --http-user=admin --http-passwd=secret http:/
+/192.168.1.1/Status.htm`;
    ($addr) = $status =~ /.*IP Address:.*?(\d+\.\d+\.\d+\.\d+)/;
    die "Can't find address" unless $addr;
    print "Address is $addr\n";
[download]

Works for me, doesn't break when I upgrade Perl...