Under very specific circumstances, php goes in tight infinite loop eating all cpu after request is cancelled.

Configuration:
php 4.2.3 as cgi
apache 1.3.27
php configured with Action directive, (important) using suexec.

Conditions for problem to occur in script:
1.ignore_user_abort(true)
2.sending any http header
3.sending any body content AFTER http header
4. connection is aborted before all data are sent to client.

Script to reproduce problem:
---- CUT ----
<?
ignore_user_abort(true);
header("X-Whatever: whatever");
?>
whatever
---- CUT ----

Problem doesn't exist with mod_php or php-cgi without suexec.
It appears that after apache has closed connection php is still trying to write output and loops for unknown reason.
I'm not sure if this is fault of php, apache or suexec, but I think it could be fixed in php.