$form = Rose::HTML::Form->new;

$form->add_fields
(
  whatever =>
  {
    type     => 'select box',
    multiple => 1,
    options  => [ 1 => 'One', 2 => 'Two', 3 => 'Three' ], 
    size     => 3,
  },
  ...
);

# Pass in form params from various sources:

# Hashref
$form->params({ whatever => [ 1, 3 ] });

# CGI object
$form->params_from_cgi($cgi); # $cgi "isa" CGI

# Apache request object (mod_perl 1 or 2)
$form->params_from_apache($r);

# Initialize the fields based on params
$form->init_fields();