SFLphone is a SIP/IAX2 compatible softphone for Linux. The SFLphone project's goal is to create a robust enterprise-class desktop phone. While it can serve home users very well, it is designed with a hundred-calls-a-day receptionist in mind.

It features a flexible client/server architecture where the GTK+ client talks to the daemon through DBus and is capable of handling multiple VoIP connections at once.

This is the graphical client for GNOME.