the 80 chars are specified in an RFC, but I can't remember which one

You can read it object by object, i.e. not \n as a input record separator, but \n\n....

my $LDIF;
unless (open ($LDIF, "<", $ldifFile)) {
  die "Error in reading '$ldifFile': $!\n";
}
else {
  local $/ = "\n\n"; # set input record separator to \n\n

  while (my $object = <$LDIF>) {
    chomp($object);
    $object =~ s/\n //g; # kill continuation lines
    print $object, "\n\n";
  } # while

  close ($LDIF);
} # else
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well, the chomp and the print ... "\n\n" are not really necessary in this case

Or use Net::LDAP::LDIF for a better solution

or as a one-liner for windows:

perl -e "$/ = qq~\n\n~" -pe "s/\n /g" infile > outfile
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or for unix/linux:

perl -e '$/ = "\n\n"' -pe 's/\n /g' infile > outfile
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