i got master values 
session.use_trans_sid=0ff
session.use_cookies=On

(defaults from php.ini)

then, I tried to changed them in
.htaccess (i got allowoverride all):
php_value session.use_trans_sid 1
php_value session.use_cookies 0

and local value hasn't changed
in tried same with php_flag
and values as 0|1 and On|Off
still local value hasn't changed

so i used
ini_set("session.use_trans_sid",1);
ini_set("session.use_cookies",0);

and then, only local value of
session.use_cookies turned to off
but session.use_trans_sid stays off

what's the problem
with PHP 4.2.2 everything was fine

config line:
'./configure' '--prefix=/usr' '--with-config-file-path=/etc' '--disable-debug' '--enable-shared' '--with-apxs=/usr/sbin/apxs' '--with-gd' '--with-jpeg-dir=/usr' '--with-png' '--with-ttf' '--with-freetype-dir=/usr' '--with-xpm-dir=/usr/lib' '--enable-gd-native-ttf' '--with-zlib=/usr' '--enable-safe-mode' '--enable-track-vars' '--enable-ftp' '--with-mysql=/usr/local/mysql' '--with-dbase' '--with-gettext' '--enable-trans-sid'