Models in 3.0.6

Hi,

I've been using CI for a number of years.

I'm upgrading all my sites to 3.0.6 and having problems with models.

Unable to locate the model you have specified: Blog

I'm even getting this message with the tutorial model

The model file name is blog_model.php

It is a copy of the "What is a Model" code from the tutorial.

It is being called from the Welcome controller with

Code:

public function test()
{
$this->load->model('blog');
}

Can someone confirm that 3.0.6 models are okay and/or point out where/if I am having one of those "moments"