On Thu, Aug 28, 2008 at 1:37 PM, Gang Liu <gangban.lau at gmail.com> wrote: > Yes? I found so many UA sent at this way. > > Could you tell me which part of RFC define this? Thanks > > See Table 1 in Section 19.1.1, page 152. True that many UA disregard this though. Cheers Benny -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20080828/072f651c/attachment.html