I attempted to run the code myself, and with a few tests it appeared to work. As it is, the only warning I received was when the port was down, $checkpoint is undefined.
Could you perhaps give us a little more detail as to what isn't working? Are you receiving any error messages?
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#!/usr/bin/perl
@==qw/p e r l m o n k s/;$|*=1;@;=qw/8 15 7 9 -1 7 7 2 0/;
foreach$-(@=){for(++$|..$;[$:++]){$-++}$..=$-}$.=~s/m/l/g;
$*=$;[4]+1;for($;[9]..$;[0]/2){$,.=substr($.,$*++,1);$*++;
}print$,;#http://www.perlmonks.org/index.pl?node_id=98506;