I have a VFP 6.0 Orders Processing application which is currently being converted to the Web. I'm using ASP+VFP COM DLLs and my front-end is a web browser. During the conversion some customers demanded an off-line application which could be used in replacement of the on-line version. In my Business objects (VFP COM DLLs) I have two methods that handle the insertion of Orders and their details. e.g:

InsertOrder() -> Inserts the order handle. and
InsertItem() -> Inserts **ONE** item each time

Both methods are stateless and my data are DBF free tables.

My problem is that I can't assure transaction between the call to InsertOrder() and the various calls the InsertItem().

I'm having problems with my off-line version in guaranteeing ACID properties for my business process (some Orders are beeing inserted with the wrong number of items -less than the correct).

I could think about using MTS and the object context, but as my methods are stateless and VFP isn't DTS-aware, I'm very confused.
I thought of XML messages which would contain both the header and the detail lines to be received by the methods and from there use VFP native transactions.
I'd like some suggestions from you about a feasible strategy. Can you help me?