Intel and Nokia are on the oFono
Intel and Nokia are getting together to work on a GPL2 licensed stack for mobile telephony applications. The project is dubbed oFono and aims to produce an open source layer between the low level modem interfaces and mobile applications which will handle calls, select networks and distribute information between the users applications.
A high level architecture diagram shows the applications connecting through the D-Bus API to the oFono stack. D-Bus, as used by Qt 4 and GNOME, allows applications to register for messages or offer services to other applications. At a low level, a plug-in API will allow for open source third party telephony stacks to be used. The developers have set themselves the goals of producing a consistent, minimal, easy to use and complete layer to make development of mobile applications and devices simpler, with oFono taking care of the "core logic".
Source code for oFono is already available, as is a mailing list with an #ofono IRC channel on irc.freenode.net being set up.