Can't Get FormBuilder to do an INSERT

I'm having trouble getting DB_DataObject_FormBuilder to generate an INSERT statement when creating new records. It always ends up generating an UPDATE statement like this: ----------------------------------------------- UPDATE expertise SET expertise = 'yeahyeah' WHERE expertise.expertise_id = IS NULL ----------------------------------------------- Here's some sample code that I am using to isolate this problem: ----------------------------------------------- $obj = DB_DataObject::factory('Expertise'); $formBuilder = DB_DataObject_FormBuilder::create($obj); $form = $formBuilder->getForm(); if($form->validate()) { $form->process(array(&$formBuilder, 'processForm'), false); echo "Should have done an insert, but it probably did an update."; } else { echo $form->toHtml(); } ----------------------------------------------- This generates a form with these fields: ----------------------------------------------- <input name="expertise_id" type="hidden" value="" /> <input name="submit" type="hidden" value="1" /> <input name="expertise" type="text" /> <input name="__submit__" value="Submit" type="submit" /> ----------------------------------------------- I'm using the latest CVS version of FormBuilder and have traced the problem to this block of code in FormBuilder.php at line 2128 ----------------------------------------------- $action = DB_DATAOBJECT_FORMBUILDER_QUERY_FORCEUPDATE; if (!isset($this->_do->$pk) || !strlen($this->_do->$pk)) { $action = DB_DATAOBJECT_FORMBUILDER_QUERY_FORCEINSERT; } ----------------------------------------------- The expected action is that this would evaluate to true and set $action = DB_DATAOBJECT_FORMBUILDER_QUERY_FORCEINSERT but it never goes into that block and $action always remains equal to DB_DATAOBJECT_FORMBUILDER_QUERY_FORCEUPDATE Here's the dump of the the data in $this->_do->$pk at the time of the if() statement in question ----------------------------------------------- [expertise_id] => DB_DataObject_Cast Object ( [type] => sql [day] => [month] => [year] => [value] => NULL ) ----------------------------------------------- According to the documentation for the FormBuilder.php processForm() function "If the primary key is not set or NULL, it will be assumed that you wish to insert a new element into the database, so DataObject's insert() method is invoked." Should the primary key 'expertise_id' be a 'DB_DataObject_Cast Object' at this point? Could that be the problem? If so, any thoughts on how/why it is getting cast that way? What am I missing here? I feel like there must be something very basic that I'm missing since the insert/update part of FormBuilder is one of it's core features. Thanks for any help. - Jamie