Location of Export file in Direct Mail

Hi,

I'm trying to find how I can access the export file from a Direct Mail, in order to send it automatically (with a workflow) to a DM service provider... easy job in ACC, but I can't find it in ACS?

Already tried to use a "wake up workflow" in the DM router, and trying to read the $(vars/@filename) in the workflow, but the workflow doesn't seem to get triggered...

Any hints?

Thanks,

Stefan