sub new {
    my $class  = shift;

    # allow hash ref as first argument, otherwise fold args             
    # into hash
    my $config = defined $_[0] && 
          UNIVERSAL::isa($_[0], 'HASH')
          ? shift : { @_ };

    no strict 'refs';
    my $debug = defined $config->{ debug }
                      ? $config->{ debug }
              : defined $config->{ DEBUG }
                      ? $config->{ DEBUG }
                      : ( ${"$class\::DEBUG"} || 0 );

    my $self = bless {
        _ID    => $config->{ id } || $config->{ ID } 
                  || $class,
        _DEBUG => $debug,
        _ERROR => '',
    }, $class;

    return $self->init($config)
        || $class->error($self->error());
}