Appcelerator's Titanium and Yii

Does anyone know if it’s possible to use the Yii framework in appcelerator’s Titanium? They claim to have full PHP support, but until now none of the frameworks I tried worked and I really would like to use Yii :(

I had to do a couple of tweaks and it still didn’t work. If I create a new WebApp and run, only the initial page works. If I click any of the other links (About, Contact, Login) I get the error message:

Fatal error: Class ‘CException’ not found in …\framework\YiiBase.php on line 138

I forgot to mention that it’s a desktop project.