[OpenSER-Users] Aliases for outgoing calls

Hello, I'd like to permit our subscribers to have several aliases for outgoing calls (basically, several number in the PSTN). I think they could set this in the header From of the INVITE to us and we would identify them, authenticate them and finally relay that same alias (and not the subscriber name) to the GW (currently we permit them to have a single alias for outgoing using a field in the subscriber table). I can see the module alias_db can be used to manage aliases, but I understand it can only be used for incoming calls as it provides just a single function alias_db_lookup that operates on the Request-URI. Any ideas? regards, takeshi