Date values cleared, instead of saved when updating a node when $form['myfield']['#access'] = FALSE

Updated title.

Same issue under -dev.

Added some documentation.

Updating title.

@doana, not sure if anyone is working on this, so make your voice heard and hopefully we can get some eyes on this.

For me, I've had to remove the use of date for my module because of this problem. I've replaced it with an interger input field which is a unix datetime. I've also added some javascript to provide the calendar popup interface.

function mymodule_form_myform_alter(&$form, &$form_state) {
  if(isset($form['field_expiry_date'])) {                                               
    drupal_add_library('system', 'ui.datepicker');
    drupal_add_js('jQuery(document).ready(function ($) {                                
      var value = $("#edit-field-expiry-date-und-0-value").val();
      if(value) {                                                                   
        var date =  $.datepicker.parseDate("@", value * 1000);                        
        $("#edit-field-expiry-date-und-0-value").val($.datepicker.formatDate("yy-mm-dd", date));
      }
                                                                             
      $("#edit-field-expiry-date-und-0-value").datepicker({
        dateFormat: "yy-mm-dd",                                                     
      });

      $("#job-node-form").submit(function() {
        var value = $("#edit-field-expiry-date-und-0-value").val();
        if(value) {
          var date =  $.datepicker.parseDate("yy-mm-dd", value);
          $("#edit-field-expiry-date-und-0-value").val(parseInt($.datepicker.formatDate("@", date) / 1000));
        }
      });                                                                         
    });', 'inline');                                                                                      
  }
}

Then I'm using this snippet, so that views provides me with the unix datetime to use in my filters:

function mymodule_views_data_alter(&$data) {                                             
  // This appears to work, for getting current unix time on the field i need 
  if(isset($data['field_data_field_expiry_date'])) {
    $data['field_data_field_expiry_date']['field_expiry_date_value']['filter']['handler'] = 'views_handler_filter_date';
  }
}

I may release this little node as a light weight/simple alternative to the date module, but really, if this is fixed in date, it wouldn't be an issue. Plus I really enjoy date_api.module for working with my dates...

If anyone has access to date module maintainers, please let them know about this issue.

@das-peter from me looking into the code, it looks like quite a few things needs to get re-factored to resolve this issue.

In my opinion currently, it appears that date module is doing certain things out of order, which is causing this problem. Perhaps Drupal itself has some issues in core as well.

Problem exists from hacking layers and layers of fixes for other issues, creating thing one.

At least from my research digging into this.

Needs someone with a good understanding of Drupal Form API & The Date module to get fixed. Anything I could do, would most likely break other things.

For me, it's a release blocker. I've had to stop using the module. I need the ability to restrict the end user from modifying the value in this date field, as it's tied to payments. If someone smart decides to manipulate the hidden value, then they can get all sorts of free goodies.