PHPUnit Bootstrap with PHP Autoload

I have a scenario wherein after upgrading PHPUnit 3.4.11 to version 3.5.3, an existing bootstrap file for phpunit suddenly encountered an error complaining about class was not found. It seems PHP __autoload is not working.

After few experiments, a solution came up as shown below.

This is the previous method of autoloading class.

if (!function_exists('__autoload')) {

    function __autoload($class) {

        $file = str_replace('_','/',$class.'.php');

        //Suppress errors in case it can't find the file.
        @include_once $file;

    }
}

Now here is the new version that works for PHPUnit 3.5

function autoload($class) {
    $file = str_replace('_','/',$class.'.php');
    try{
        include_once $file;
    } catch (Exception $e) {

    }
}
spl_autoload_register('autoload');