it would be really great if this module had an "onclick" field
Just add this in "menu_attributes_menu_attribute_info" function
$info['onclick'] = array(
'label' => t('Onclick'),
'description' => t('Enter an onclick event.'),
'form' => array(
'#type' => 'textarea',
'#rows' => 2,
Check the patch provided at http://drupal.org/node/1923740.
Closing as duplicate even though the other issue is newer, but it has a patch.
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