PhpPgAdmin login weird...

Hi,

My webserver work in PHP4, safemode and it's running for years.

I use Debian, kernel 2.6 since yesterday.

I install psotgreSQL and PHPPGADMIN from apt-get (in .deb package) like
always on Debian...

I configure pg_hba.conf with
local postgres trust

I configure config.inc.php (from phppgadmin) to
 $conf['extra_login_security'] = false;   at this moment.....

Problem:
When I log in phppgadmin with postgres without password, I enter in a 3
frame page... with the login form in each frame.  I log in each frame, I
see the right frame.  I clic anywhere, the login reappear... if I log, I
see the page...

I have no error in phperror log.
I have no error in postgresql log.
I have no error in apache log.

I look in phppgadmin source code... and I think it's a problem with
session?  like if they are not memorized.  But... in the directory where
php4 save session, the file is there and datas are good in it.

Someone have a clue?

thanks.