There are few good values which should be change for specific script. Use following code in .htaccess to changes the values as per your requirement.
php_flag session.use_trans_sid off
php_flag session.use_only_cookies on
php_flag register_globals On
php_value magic_quotes_runtime Off
php_flag magic_quotes_gpc off
php_admin_flag safe_mode Off
php_value post_max_size 20971520
php_value upload_max_filesize 12M
php_value max_execution_time 600
php_value magic_quotes_gpc off
php_flag session.bug_compat_warn off
php_value session.use_cookies 1
php_flag session.use_only_cookies 1