Tell me reason and How to do it

After installed PHP4.3.2 and runned my main page, this error information will display as follows, Security Alert! The PHP CGI cannot be accessed directly. This PHP CGI binary was compiled with force-cgi-redirect enabled. This means that a page will only be served up if the REDIRECT_STATUS CGI variable is set, e.g. via an Apache Action directive. For more information as to why this behaviour exists, see the manual page for CGI security. For more information about changing this behaviour or re-enabling this webserver, consult the installation file that came with this distribution, or visit the manual page. PHP Warning: Unknown(): gd: Unable to initialize module Module compiled with module API=20010901, debug=0, thread-safety=1 PHP compiled with module API=20020429, debug=0, thread-safety=1 These options need to match in Unknown on line 0 please tell me reason and how to correct it, thank you, Michael