Two new SIP Servlet Container APIs were delivered in the 18.104.22.168 version of the Communication Enabled Applications (CEA) Feature Pack and are also now available in the latest WebSphere V8 Beta. For those of you who didn't know, all the features delivered in the CEA Feature Pack including the JSR 289 compliant SIP container are being rolled into WebSphere version 8.
The two new APIs are:
1) A new API for dynamic control of SIP message timers. This API is used for setting SIP message timers on a message-by-message basis. It allows applications to specify different timer settings on a message-by-message basis by setting a proprietary header in an outgoing SIP message. This feature can only be used to modify SIP timer settings for outgoing SIP Request and only affect Timer B and Timer F which are defined as part of RFC 3261.
2) A new library which provides SIP application developers with access to RFC 3263 functionality. RFC 3263 defines a standard for accessing SIP specific NAPTR records from a DNS server. Support for this RFC was added into the WAS 7 SIP container but was hidden from application developers. Instead, the container uses this library to look up SIP URIs for outbound request on an as needed basis. This new API provides direct access to these capabilities from a SIP application using either a blocking, synchronous API or a non-blocking, asynchronous API.