WordPress function to add the TinyMCE WYSIWYG editor to any custom field of type 'Textarea'

gistfile1.txt

// important: note the priority of 99, the js needs to be placed after tinymce loads
// important: note that this assumes you're using http://wordpress.org/extend/plugins/verve-meta-boxes/
// to create the textarea - otherwise change your selector

function admin_add_wysiwyg_custom_field_textarea()
{ ?>
<script type="text/javascript">/* <![CDATA[ */
	jQuery(function($){
		var i=1;
		$('.verve_meta_box_content textarea').each(function(e)
		{
		  var id = $(this).attr('id');
		  if (!id)
		  {
		   id = 'customEditor-' + i++;
		   $(this).attr('id',id);
		  }
		  tinyMCE.execCommand('mceAddControl', false, id);
		});
	});
/* ]]> */</script>
<?php }
add_action( 'admin_print_footer_scripts', 'admin_add_wysiwyg_custom_field_textarea', 99 );