Failure to display error message when dataroot not defined

[guy thomas]

If I have a config without a valid data root then I should see:

Your defined data root directory, /path/to/uploaddir/, is not writable. This means that neither session data, user files nor anything else that needs to be uploaded can be saved on your server. Please make the directory if it does not exist or give ownership of the directory to the web server user if it does.

But instead I see:

Fatal error: Class 'Session' not found in /vagrant/www/joule2/mahara/lib/errors.php on line 130
Call Stack
# Time Memory Function Location
1 0.0118 597352 exception( ) ../errors.php:0
2 0.0118 597776 MaharaException->handle_exception( ) ../errors.php:518
3 0.0118 599376 log_message( ) ../errors.php:593

[Mahara Bot (dev-mahara)]

What version of mahara did you have?