I'm using authorize.net and the order_id is not being sent.
In authorize.php, the _loadStandardVars loads $order->order_id into $vars["x_invoice_num"] if order_id is not empty. However, it appears this is called before order_id is set.
I've verified that x_invoice_num is correctly transmitted to authorize.net when order_id is set by hardcoding text into $vars["x_invoice_num"] in the _loadStandardVars function. However, I don't know where the class is called from and haven't found other code to figure out where the problem is. Any suggestions on how to make this work? Thanks!