Why would mysqli connect (to remote server) work on the php command line and not through apache when both CLI and apache php are using the same php.ini file?

When I run the attached code snippet from the command line (php mysqltest.php) the code works and a connection to the remote DB is successful. When I run this same code snippet via apache I get the following error:

Warning: mysqli::mysqli() [function.mysqli-mysqli]: (HY000/2003): Can't connect to MySQL server on '192.168.3.100' (13) in /var/www/tuneup_server/ts_00_02_00/html/index.php on line 5

Fatal error: Uncaught exception 'Exception' with message 'Connection Failed: Can't connect to MySQL server on '192.168.3.100' (13)' in /var/www/tuneup_server/ts_00_02_00/html/index.php:6 Stack trace: #0 {main} thrown in /var/www/tuneup_server/ts_00_02_00/html/index.php on line 6

The server this code is running on is at 192.168.3.102. What is the difference? Is it the fact that these processes are run with different users?

PHP: 5.2.5
MySQL:  5.0.22
OS: Redhat Enterprise Linux 5

$connection = new mysqli('192.168.3.100', '<user>', '<pass>', '<db name>');
if(mysqli_connect_errno()) throw new Exception('Connection Failed: '.mysqli_connect_error());

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