(Edit: See particle's comment; all that's missing is an '*' on the locals... Removed my questions wondering why it didn't work.)

Here's a version that works for me. I reduced the limits so it didn't spam quite as much :)

#!/usr/bin/perl
use warnings;
use strict;

my ( $ppid, $in, $out) = $$;
pipe ( $in, $out) or die $!;

# "Daemon"
{
    #local STDIN = $in;
    local $| = 1;
    my $child;
    defined( $child = fork) or die $!;
    last if $child;
    close $out or die $!;
    while (<$in>){
        print "Parent got: $_";
    }
    exit 0;
}

# Spawn some client processess
{
    #local STDOUT = $out;
    select($out);
    local $| = 1;
    for my $kid (1..10) {
        my $child;
        defined( $child = fork) or die $!;
        next if $child;
        close $in;
        select( undef, undef, undef, .001)
          while kill $ppid, 0;
        select( undef, undef, undef, rand(1000)/1000),
          print 'Child ', $kid,
                ' pid=', $$,
                ' message=', 0 | rand 10000,
                $/
          for 1..20;
        exit 0;
    }
}
[download]

--
Mike
(Edit: Added 5.6.1-friendly version of code)