The Accept-Language header field is used in requests to indicate the
preferred languages for reason phrases, session descriptions, or
status responses carried as message bodies in the response.
This interface provides factory methods that allow an application to create
Address objects, URI's, SipURI's and TelURL's from a particular
implementation of this specification.
Send a transaction timeout event to the application if Tx is still in Calling state in the
given time period ( in base timer interval count ) after sending request.
The class handles authentication challenges, caches user credentials and takes care (through
the SecurityAuthority interface) about retrieving passwords.
The Authorization header is used when a user agent wishes to authenticate
itself with a server - usually, but not necessarily, after receiving an
UNAUTHORIZED Response - by including an AuthorizationHeader with the
Request.