Use hook form alter to change input type I am trying to change the input type on an ubercart checkout form using hook_form_alter. I added an extra field using the uc cart extra fields pane module but there is no option to add e-mail - only text - and I need the field I added to validate as an e-mail. 

The field in question is:

&lt;input type="text" id="edit-panes-billing-address-billing-ucxf-bill-to-email" name="panes[billing][address][billing_ucxf_bill_to_email]" value="" size="32" maxlength="255" class="form-text required"&gt;


The code I am using but with no success is:

function MYMODULE_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  if ($form_id == 'uc-cart-checkout-form') {
    form['panes-billing-address-billing-ucxf-bill-to-email'][LANGUAGE_NONE][0]['type'] = 'email';
  }


Thanks for any assistance!
If you want alter a form via an ID check you should be using $form_id == 'uc_cart_checkout_form'. Drupal form generation functions don't use "-" characters like generated CSS id/class attributes.