Mmmm... really? what if there is no way to reproduce the bug with the official kernel because the application simply won't work on that setup? is there any hope for customers in this situation?.
Likewise, is there any support if I take a RHEL 5 box and update PHP to 5.2 or 5.3, or maybe if I decide to downgrade to PHP 4.3 (the same in RHEL 4) because it's really hard for us to test our huge web system and validate it against the newest version of PHP?.
If there is any link on the Red Hat website that explains this kind of scenarios it would be very handy for me and my company.