Fatal error: Call to undefined function...

I recently installed Apache 1.3.33, PHP 5.0.4, and MySQL 4.1.12 on Fedora Core 4. Here are the configuration settings before I compiled: Apache: ./configure -enable-module=so PHP: ./configure -with-mysqli=/usr/local/mysql/ --with-apxs=/usr/local/apache/bin/apxs MySQL: (none) Everything seems to work fine, except for when I use a non-core PHP command. For example, <?php echo 'This works just fine'; ?> works fine. Yet <?php mysql_connect( . ) ?> or <?php CreateImageTrueColor(100, 100) ?> will not work. I receive "Fatal error: Call to undefined function <function name> in <file name>. It seems as though PHP is not able to find the relevant PEAR functions. Why this is I have no idea and any assistance would be greatly appreciated. Thanks in advance, Joshua C.