Asterisk Developer team has released the latest release candidate for Asterisk 1.6.0 Branch. The release takes care of some issues like;
* Properly ACK 487 responses to canceled INVITEs. Reviewboard
* SIP registration authorization loop caused by stale nonce.
* Ensure outbound NOTIFY requests are properly routed through stateful proxies
* Resolve no audio on chan_dahdi calls until DTMF is sent by caller
* Removed confusing warning message in chan_misdn.
For a full list of changes in this release candidate, please see the ChangeLog.
Release note : Asterisk 1.4.26-rc6 released