an error before register a session

Dears,When i run "rm -rf /tmp/sess_*" ,It are meaning that i clean every session. When i want to my program,I receive following warning : Warning: Unknown(): Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0 But,When i regist at least 1 session,I don't recv it. Please guide me.... Yours,Moshen ===== ---------DIGITAL SIGNATURE------------------- ///Mohsen Pahlevanzadeh//////// Network administrator & programmer My home phone is: +98213810146 My email address is m_pahlevanzadeh at yahoo dot com My website is: http://webnegar.net ---------------------------------------------------------------- _______________________________ Do you Yahoo!? Win 1 of 4,000 free domain names from Yahoo! Enter now. http://promotions.yahoo.com/goldrush