I (www.jamesbarnsley.com) found that when using the Yii Bootstrap tabs component you will sometimes want to direct the user to a specific tab and not necessarily the first tab. Yii Bootstrap already provides the "active" variable so you can define whether the tab is the active tab or not in PHP. I generally find though that a PHP solution to this problem is rather cumbersome as every tab component will need the PHP code inserted or you will have to extend the tab component somehow to do it.
There are several methods and techniques that come handy in the case you need to call an external resource periodically or if you are waiting for a server push, but I present here an easy and straightforward one using HTML5's Server-Sent Events (SSE).
Update: This wiki has been rewritten to be in line with Yii 1.1.14. Since many of the detailed complexities are now handled by Yii, the article focuses on how the crypt() built-in function works and why it's important to use it correctly.