Here is a SIP deskset with Bluetooth that lets you take hands-free calls with your favorite headset. The VTech ErisTerminal VSP875G comes with a 4.3″ tiltable color LCD display. It has HD audio and programmable buttons. Plenty of feature keys are available to make your life easier.
The VSP875G SIP Deskset supports 12 SIP lines. It also has electric hook switch support. You can find out more information about it here.