Running scripts via CLI

Hello

When i follow the documentation regarding running CLI scripts everything works fine

http://www.codeigniter.com/user_guide/ge...hlight=cli

However when i autoload the database library I get a database error (see attachment)
The database login details are correct because the rest of the app works fine

A partial workaround is to not autoload the database library and to load in in the constructor of each individual controller. But what happens if the controller  function being run on CLI needs to access the database??

Thanks in advance for any help!