PHP, sessions and SUSE 9.1

Hello people, I have a PHP script that used to work fine in apache 1.3.x. Yesterday, I install SuSE 9.1 and my script stop working with Fatal error: Call to undefined function: session_name() By Google, I found that phpinfo() could show me the truth and it was there : PHP Version 4.3.4 Build Date May 7 2004 18:42:35 Configure Command './configure' (...) '--disable-session' (...) So, why the hell php4.rpm from SuSE 9.1 was compiled without support for sessions? How I can enable this without breaking rpms? I suppose I have to install PHP4.src and then, compile --with-session, but what file(s) do I have to substitute (only /usr/bin/php?)? Thanks