In a module I'm creating, I'm embedding the subqueue edit form from the Nodequeue module, and I need to replace the title with a text field and use a custom theme function (overriding theme_form_element) for the textfield. I've registered my theme function with hook_theme: /** * Implementation of hook_theme */ function mymodule_theme() { return array( 'mymodule_subqueue_title' => array( 'arguments' => array($element => NULL, $value => NULL), ), ); } And then call it in my hook_form_alter" $form[$item->nid]['item_title'] = array( '#default_value' => $item->title, '#type' => 'textfield', '#size' => 10, '#maxlength' => 50, '#theme' => 'mymodule_subqueue_title', ); and define my function: function theme_mymodule_subqueue_title($element, $value) { The problem I'm getting is this error message: Missing argument 2 for theme_mymodule_subqueue_title() in .../sites/all/modules/custom/feature_package/mymodule.module on line 450. I'm guessing the problem is in how I define my arguments in hook_theme. Is that what I'm doing wrong, or is it something else? Thanks, Steve