I am pretty sure that Obihai has a web-based tool you can use to do that. I haven't used it myself, so I don't know how difficult it is (whether you need to understand XML or if it is menu-driven). The tool is designed for service providers and enterprise customers. Send an email to
support@obihai.com, and describe your installation. I'm sure they will be glad to help a customer who has purchased a large quantity of their phones.