Hi friends I need your help configure Cisco 3745 router which is installed with 2x FXO and 4x FXS ports and have latest 12.4 voice IOS. Both two FXO ports will be connected to BT (UK Telco) as external lines and all four FXS ports will be connected to standard analogue phones as internal extension lines. All internal extensions should communicate each other plus all can have access to external lines by pressing 9. I am looking for your help as step by step configurations also please keep in mind to resolve FXO supervisory disconnection issue specific to BT UK. I will be highly thankful for your kind help.