Tracking development of pjsip, the Open Source SIP, media, and NAT traversal stack/SDK/library for Android, iOS, Windows, Linux, MacOS, RTOS, embedded, and pretty much anything, any device.
Also check PJSIP Documentation site.
Turns out that the previous release was not so much of a good news after all.
Several people had reported several build problems, especially on Mingw, and also on Windows Mobile, due to the recent addition of multicast constants in PJLIB socket abstraction.
We apologized for the problem (and quite humiliated too), hopefully we’ve learnt our lesson and this will not happen again in the future. In the meantime, please find the update in the download page.
Here is where we talk about pjsip development in general, and maybe other stuff as well. For the project itself, please go to the main pjsip project website. or pjsip documentation.
PJSIP is backed by Teluu, which provides professional support, additional licensing options, and a network of qualified consultants.
pjsip blog 
One response to “Version 1.0-rc4 is released”
hi,
I’m using the PJSIP stack downloaded from http://www.pjsip.org/release/1.0/pjproject-1.0.zip and meet some problem with making a sip call.
When the call has been successfully made(the “m” functionality), some high frequency noise belong with some echo effect can be heard from each phone’s “loud speaker”. Same problem also occurred in the loopback functionality(press “l”).
To reproduce the problem, pls follow the steps below:
1) download http://www.pjsip.org/release/1.0/pjproject-1.0.zip and port into Carbide 1.3 with “bld.inf”.
2) rename [root]\pjproject-1.0\pjlib\include\pj\config_site_sample.h to config_site.h
3) change SIP_DST_URI, SIP_DOMAIN , SIP_USER , and SIP_PASSWD in ua.cpp(pjproject-1.0\pjsip-apps\src\symbian_ua\)
4) install “symbian_ua” on target device. i’ve test on Nokia 6220, Nokia 6110, Nokia E70.
5) launch “symbian_ua”. Now u should see that u’ve successfully registered.
6) press “l” to test the “loopback” functionality. Now u should hear some high frequency noise belong with some echo effect.
Thanks in advance,
BR,
John