When looping through child_class_helpers, the key is assigned to the $name variable, which is already used as the property name. The following code solves this issue by using a different key variable in the loop:

					// add the child class helpers to the record
					foreach($joined_model->child_class_helpers as $hname => $hclass)
					{
						$obj->$hname =& new $hclass($o);
					}

Cheers,
Stan