Just following the formulas on the web page: 
sub ip_to_dotless {
        return 0+ eval " 0x" . sprintf("%02x%02x%02x%02x", split(/\./,
+ shift));
}
sub dotless_to_ip {
        my $hex=reverse sprintf("%x", shift);
        my @ip;
        for(0..3) {
                push(@ip, 0+ eval "0x" . reverse substr($hex, 0, 2, ""
+));
        }
        join('.',  reverse @ip);
}

[download]
This seems to work nicely.

In reply to Re: Dotless IP address problem by clintp
in thread Dotless IP address problem by Ovid

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