How do you set the focus of a TinyMCE textarea element?

Finally found an answer… use the command:

tinymce.execCommand('mceFocus',false,'id_of_textarea');

For my purposes, ‘id_of_texterea’ was “description”, ie

<textarea id="description" ... ></textarea>

In the form element that preceded my textarea, I added the execCommand above to the element’s “onblur” action.