Migration of log features from 7.4 to 8.0

Dear Gurus,

Please show me to the right manual/discussion if my questions are already
answered/solved.

1. DEBUG message level separation:

In v7.3 there were the annoying DEBUG messages Start/CloseTransactCommand.
In v7.4 you could eliminate them from user DEBUG messages by logging from
DEBUG2 level.
In v8.0.0rc4, they are back at DEBUG2 level.

Is there a way to eliminate them AND keep user DEBUG messages (i.e.
plpgsql's "RAISE DEBUG")

2. CONTEXTs and HINTs

Looked up all the lines in postgresql.conf, but couldn't find the one to
turn CONTEXT and HINT lines after notices or errors. They proved to be very
useful, but can't make them be logged in v8. Is there a way?

3. redirect_stderr bogus?

Activating redirect_stderr, setting log_dir, log_file and all the rotate
params, it looked to me that all output the logger produced were 'db system
ready' and 'shut down', and not even these lines appeared in the log file.
May it be a bug, or simply the fact that a nonempty file already existed
(from redirected stdout, as described above)<

TIA,
--
G.