[Users] Complete Config

Hey All, I am looking for someone who can give me some assistance with a building an openser configuration that is able to handle the following: 1) Multiple domains. 2) Mediaproxy for all clients (not just clients behind NAT). 3) RADIUS accounting for calls. 4) Least Cost Routing for selecting the cheapest upstream link. 5) Trusted (non-authenticated) upstream providers for receiving calls. 6) Call Redirection (all calls, busy, no answer) with redirected calls billed to the redirecting party. 7) Some network features, like voicemail, talking clock, etc, sent to an Asterisk machine. I currently have a configuration that does (1) through (5), but have had no luck in even getting call redirection to work, let alone getting the billing right. I'm having some issues, like: - Getting two replies to REGISTER messages which causes Asterisk clients to print a message "Got authentication request (401) on unknown REGISTER to <...>" - Sometimes I get a storm of CANCEL or BYE messages when a call is ending. I have absolutely no idea where the messages are coming from, whether its the client or upstream, and what message I'm sending that's causing it. The configuration I have made is just from reading the docs, looking at the howtos and tutorials and from guessing what should be done. I think the problems I'm having are related to not really understanding what should be happening 100% and having a config that is a lot more complicated than it needs to be. Anyone willing to give me some assistance? I can send a password sanitised copy of my current config directly if it would help. Regards Darryl