We are working on a billing solution for use with SER. We have completed a great PrePaid Billing solution for a client V1010.com but they currently only do outbound and arent planning to do inbound for a time. We are looking for some sample inbound call data from PSTN if anyone has some we would appreciate it! We can handle all Country codes and Area Code rates as well as custom rates as of now. So hope to have monthly billing completed soon.