Follow the steps above precisely – particularly the advanced NAT and codec priorities – and you will achieve a “full” functional VoIP client exactly as Nokia intended for firmware version 1.0. Do not expect HD voice, encryption, or modern features, but enjoy the quirky charm of 2010‑era mobile VoIP. Archived reference: Symbian^3 Developer Library v1.0 (2010), “Internet Telephone Settings Configuration 3.1” – Nokia Corporation.
It is important to clarify upfront: Symbian OS is no longer supported, and its VoIP stack relies on obsolete SIP (Session Initiation Protocol) standards and security ciphers. sip voip 3 1 settings symbian 3 v1 0 en full