#### from CGI/Util.pm
sub escape {
  shift() if ref($_[0]) || (defined $_[1] && $_[0] eq $CGI::DefaultClass);
  my $toencode = shift;
  return undef unless defined($toencode);
    $EBCDIC = "\t" ne "\011";
    if ($EBCDIC) {
      $toencode=~s/([^a-zA-Z0-9_.-])/uc sprintf("%%%02x",$E2A[ord($1)])/eg;
    } else {
      $toencode=~s/([^a-zA-Z0-9_.-])/uc sprintf("%%%02x",ord($1))/eg;
    }
  return $toencode;
}