Nortel supplied the VoIP and IMS-ready technology 
The fixed-mobile convergence (FMC) solution for Neuf Cegetel includes Nortel’s IMS-ready Multimedia Communication Server 5200 (MCS 5200) which seamlessly integrates voice with video, collaboration, and presence services. This solution leverages SIP to enable service providers to deliver seamless handover between cellular and WiFi technologies and create new revenue-generating opportunities for service providers.
Nortel’s IMS solution is access-aware and supports 3GPP (IMS), 3GPP2 (MMD), Packet Cable 2.0 and TISPAN standards.
http://www.nortel.comhttp://www.neuf.fr