Null values being interpreted as 0

I found more bugs relating to the bug I reported last week (http://drupal.org/node/1031994). I ran into this when I realized that unchecking "Private" didn't work -- going back to the node I just saved still had the value checked.

Simply put, null values are being interpreted as 0 values. I think I found them all. I am using 1.0, not DEV, so I will explain what I fixed here:

PRIVATE

Was:

$form['og_private']['#default_value'] = ($node->og_private) ? $node->og_private : $og_private;

Now:

$form['og_private']['#default_value'] = (isset($node->og_private)) ? $node->og_private : $og_private;

MENU

Was:

$form['og_menu']['#default_value'] = ($node->og_menu) ? $node->og_menu : $og_menu;

Now:

$form['og_menu']['#default_value'] = (isset($node->og_menu)) ? $node->og_menu : $og_menu;

LANGUAGE

Was:

$form['og_language']['#default_value'] = ($node->og_language) ? $node->og_language : $og_language;

Now:

$form['og_language']['#default_value'] = (isset($node->og_language)) ? $node->og_language : $og_language;

DESCRIPTION

Was:

$form['og_description']['#default_value'] = ($node->og_description) ? $node->og_description : $og_description;

Now:

$form['og_description']['#default_value'] = (isset($node->og_description)) ? $node->og_description : $og_description;