\section{Changes in Version -12}

Since version -11, the following changes have been made.  These changes
reflect IESG comments. 

\begin{itemize}
\item Section 16.3 was missing \header{Content-Type} header.

\item The DNS search procedure has changed. Reference to CNAME lookups
has been removed since their usage is implicit in normal DNS
procedures. Also, automatically appending a sip. to the domain name in
the URL before lookup has been removed. A note has been added
discussing the creating of SIP URL's from email addresses and
encourages the usage of rfc2219.

\item Semicolon removed from user and password BNF in SIP URL.

\item An email address for IANA registrations is now listed.

\item For the ``Moved Temporarily'' redirect response, no default value
for the expiration of this address is specified. This has been
clarified; the redirected address is only valid for the duration of
the call. This is consistent with exising text under the
\header{Contact} header description which indicates that the values
should not be cached.

\item Clarification that {\CANCEL} and {\ACK}'s should have the same
\header{Via} branch parameter as the request they cancel or acknowledge.

\end{itemize}
