Submit handlers being called

I am creating an 'add new element' button in hook_form for a module I am building that creates a new node. The button works - when I click it, new textfields are added to the page. The problem is that the submit handlers are being called when the button is being clicked. Here is the relevant code:

[code]

$form['pos_wrapper']['pos']['noun_fieldset']['counters_wrapper'] = array
(
	'#prefix' => '<div id="counters_wrapper">',
	'#suffix' => '</div>',
);
$form['pos_wrapper']['pos']['noun_fieldset']['counters_wrapper']['counters_count'] = array
(
	'#type' => 'value',
	'#value' => (isset($form_state['values']['counters_add_more'])) ? $form_state['values']['counters_count'] + 1 : 1,
);
for($i = 0; $i < $form_state['values']['counters_count'] + 1; $i++)
{
	$form['pos_wrapper']['pos']['noun_fieldset']['counters_wrapper']['counters'][$i] = array
	(
		'#type' => 'textfield',
		'#title' => t('Counters'),
		'#default_value' => (isset($form_state['values']['plural_form'])) ? $form_state['values']['plural_form'] : FALSE,
	);
}
$form['pos_wrapper']['pos']['noun_fieldset']['counters_add_more'] = array
(
	'#type' => 'submit',
	'#value' => t('Add another counter'),
	'#submit' => array('ahah_helper_generic_submit'),
	'#ahah' => array
	(
		'path' => ahah_helper_path(array('pos_wrapper', 'pos', 'noun_fieldset', 'counters_wrapper')),
		'wrapper' => 'counters_wrapper',
		'method' => 'replace',
		'effect' => 'fade',
	)
);

[/code]

If it matters, all the above code is not present when the form is initially rendered, and is added through an AHAH call itself.

I am also calling this code in hook_form_alter()

[code]

ahah_helper_register($form, $form_state);
$form['changed']['#default_value'] = $_SERVER['REQUEST_TIME'];

[/code]

So the problem isn't arising from the lack of that code.

I appreciate any help. Help!