Execution Time Limit or What?

I've got a PHP script that is occasionally doing a fairly long SQL query against an Oracle database. The page that returns the results of this query comes down to the browser up to the point that the query results are to be displayed and then just stops. No error message. No warning. Nothing. If I limit the query to a smaller result set then the page displays correctly. At first I thought it was an execution time out problem so I bumped up the max_execution_time in the php.ini file and restarted the Apache server, but this didn't help at all. The new value does show up when I do a phpinfo() so I know it has been changed. The page stops downloading to the browser at exactly 30 seconds, which sounds exactly like the default setting of max_execution_time. So, my questions are: Is there something else that might limit the execution time of a PHP page other than max_execution_time? Could either Oracle or Apache be the cause of the limitation? What might be the cause of not getting any PHP error/warning message output? I'm using the default settings for error_reporting (55) so I haven't disabled them and error_reporting is set to 1. My setup is: PHP 3.0.15, Apache 1.3.12, Oracle 7 all running on AIX 4.3.3 -- Brandon