JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://twitter.github.com/bootstrap/assets/css/bootstrap.css">
<a class="btn testBtn" data-toggle="modal" href="#myModal" >Launch Modal</a>

<div class="modal hide" id="myModal">
  <div class="modal-header">
    <button type="button" class="close" data-dismiss="modal">×</button>
    <h3>Modal header</h3>
  </div>
  <div class="modal-body">
      <textarea id="textareaID"data-focus="true"></textarea>
  </div>
  <div class="modal-footer">
    <a href="#" class="btn" data-dismiss="modal">Close</a>
    <a href="#" class="btn btn-primary">Save changes</a>
  </div>
</div>

JavaScript

$('#myModal').on('shown', function () {
    $('[data-focus]').focus();
})