I'm sure that this is possible in Perl, and also relatively easy, but an even easier solution is available from the shell, if you have enough diskspace to hold twice the input file:

split -1000 filename splitted
for i in (splitted*); do
  x --filename $i
  # or, if x can't be started with only a filename:
  x --filename --firstLine=1 --lastLine=1000
done
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The split command splits your file by lines, and then the shell iterates over the resulting files and calls x for each file.

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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