AMEX, CCV needs to support 4 digits

There is a note in the Authorize.net module around line 266 that CCV is not supported - this doesn't seem to be the case any longer, it is working pretty well for me at least and is a good layer of protection for merchants.

The only issue I ran into is American Express uses a 4 digit number, not 3 digit so the field size needed to change. Here was the update around line 266.

  $form['details']['ccv'] = array(
    '#type' => 'textfield', 
    '#title' => t('CCV Security Code'),
    '#description' => t('The 3 digit number on back of card, or 4 digit number on the front for AMEX'), 
    '#size' => 4, 
    '#maxlength' => 4, 
    '#required' => true, 
  );

Thanks