if (isset($_GET['debug'])) {
$order = Mage::getModel("sales/order")->load('12898');
$invoice = Mage::getModel('sales/service_order', $order)->prepareInvoice();
$invoice->setRequestedCaptureCase(Mage_Sales_Model_Order_Invoice::CAPTURE_OFFLINE);
$invoice->register();
$transactionSave = Mage::getModel('core/resource_transaction')
->addObject($invoice)
->addObject($invoice->getOrder());
$transactionSave->save();
}