2.39 [KK 2008-12-04] 
- Added Httpbuffer::reset()
- The HTTP dispatcher will show back end error returns (when the HTTP
  code is in the 400 or 500 range)
- main() will show runtime limits when invoked with -v
- The HTTP dispatcher no longer downgrades to HTTP/1.0 and closed
  connections. Webserver back ends can do this.
- Exceptions during the sending of an error page in HTTP mode are
  discarded, no longer logged.
- Mutex lock added around thread startups (see Thread::start()), when
  requested so in sys/sys.
- Mutex locks around malloc()/realloc(), when requested so in sys/sys.
- Fixed possible socket leak in TcpDispatcher::execute(). The back end
  socket might not have been closed when the dispatch phase crashed.
- Dispatchers are now derived from a new base class Dispatcher, in
  preparation for UDP handling.
- Timestamp handling centralized in a class Timestamp.
- Messaging (msg(), debugmsg(), reportmsg(), warnmsg()) centralized.
- Started threads are administered in Threadlist. Separate threads are
  killable from the web interface, or all threads to a given back end.