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This paper presents a 3-layer service architecture for the session initiation protocol (SIP) that incorporates other protocols to provide multimedia and presence communications. Beyond SIP basic services, personalized services are also addressed. To enrich presence related services, presence information is extended from the well known "online" and "offline" indicators to a much broader meaning that includes "location", "linestatus", "role" and "availability". Based on this, the call processing language (CPL) is extended to describe presence related personalized services in both call-processing systems and presence systems using information such as a person's presence status, time, address, language, or any of their combinations.