Values are defined through XML-files in the folder app/design/adminhtml/default/default/template/producttemplates/.
The folder contains some example files. At a minimum you need to create a default.xml file.
Optionally, you can create XML-files per product-type, like simple.xml.
An XML file default.xml might look like this:
<?xml version="1.0"?>
<product>
<status>1</status>
<tax_class_id>2</tax_class_id>
<weight>1</weight>
<cb_status>unknown_pending</cb_status>
</product>