ASM Custom Response Page

Hi there,

I am using a custom response page for ASM, as part of that I want to clear some troublesome persistent cookies that are triggering alerts.

I've got the following setup in the response and it seems to work correctly for a test VIP, but on the production side I can see the headers in the response but it doesn't actually clear the cookies.

HTTP/1.1 200 OK
Cache-Control: no-cache
Pragma: no-cache
Set-Cookie: ___utmvc=deleted; domain=.foo.bar; path=/; expires=Thu, 01 Jan 1970 00:00:00 GMT
Set-Cookie: testcookie=deleted; domain=.foo.bar; path=/; expires=Thu, 01 Jan 1970 00:00:00 GMT
Connection: close

I also tried using an iRule to do the same using the ASM_REQUEST_BLOCKING event but that doesn't trigger at all.

Any ideas?