The reSIProcate project has started a branch for supporting SIP over WebSockets and WebRTC solutions
reSIProcate already provides another core element of the WebRTC architecture, namely, the reTurn Server, a free and open implementation of the ICE/STUN/TURN protocols for NAT traversal. These protocols are used by WebRTC capable browsers to find the optimal way to route RTC sessions when NAT is detected. Many people perceive this as the `missing link' that existed in all earlier RTC protocols.
In parallel, Debian Developer Daniel Pocock has recently promoted the SIPml5 WebRTC SIP client as a Debian package, making it easier than ever for web servers to support WebRTC.