help wanted for install php with mysql support on windows

I use Apache1.3,php5.0(they work fine) and mysql 4.1(it also can work separately) . But when I interact with MySql using php,it says " Fatal error: Call to undefined function mysql_connect() ", I have uncommented php_mysql.dll inside php.ini and add D:\php to the system variable path, the libmysql.dll is in that path. Is there anything I should do to cope with this problem? Thank you very much! -Zheng