A problem under php4+pws+mysql

When I use php4+pws to run some php programes, an error like this often happens,"undefined variable xxx......", while the php progares run correctly on the web server, can you tell me why, is there anything wrong with my php.ini file? I know little about php programming,and I am a Chinese, please tell me about it use simple English,Thank you very much. -- __________________________________________________________________ Your favorite stores, helpful shopping tools and great gift ideas. Experience the convenience of buying online with Shop@Netscape! http://shopnow.netscape.com/ Get your own FREE, personal Netscape Mail account today at http://webmail.netscape.com/