wget --spider and ignore_user_abort(TRUE)

Hi there, I am trying to get a script to run in background no matter what, but I am obviously doing it wrong. Here is the entire code: <?php //first instruction to be sure it is parsed ignore_user_abort(TRUE); set_time_limit(3600); //sleep(10); //this will send the HTTP code + headers + test ob_start(); echo "test"; ob_flush(); sleep(10); system("touch /tmp/aborting"); ?> The file /tmp/aborting get touched if I abort the connection in a browser, or if I run "wget blabla/script.php" and kill wget... in fact it works perfectly in any way, but it doesn't work when I use the "--spider" option of wget. That option does a HEAD request and as soon as it receives the HTTP code 200 closes the connection. The script is then aborted and the file /tmp/aborting never get touched. I initially thought that ignore_user_abort() never get to be parsed because the connection is closed before and I set it in the php.ini file, but that didn't work. I then realized that PHP has to get at least to the ob_flush() call, that's proved by putting a sleep(10) just before the ob_start() call: wget --spider waits 10 seconds before exiting. Why is ignore_user_abort(TRUE) ignored, what am I missing? I probably shouldn't say that while asking for help, but... is this a bug? I am using PHP 5.2.6-pl7-gentoo via Apache 2.2.9-r1 (Gentoo) with "worker" MPM. Thank you for your help, tillo