Problem of doing both TCP and HTTP editting

With following code, I found both TCP-INSERT and HTTP Header Insertion were successfully done (checked on receiving tcpdump).

when CLIENT_ACCEPTED {
    TCP::payload replace 0 0 "TCP-INSERT"
    TCP::release
}

when HTTP_REQUEST {
    HTTP::header insert HDR "HTTP-HEADER-INSERT"
}

Unfortunately if I add a TCP insertion fired at SERVER_CONNECTED, it show an error.

I think a thorough understanding of the events and state machines internal may be very helpful to debug.

Thanks for your thought.