cond %{SEND_RESPONSE_HDR_HOOK} [AND]
cond %{HEADER:All-Cache} ="" [NOT]
    set-header All-Cache "%{HEADER:All-Cache} %{CACHE}"

cond %{SEND_RESPONSE_HDR_HOOK} [AND]
cond %{HEADER:All-Cache} =""
    set-header All-Cache "%{CACHE}"

cond %{SEND_RESPONSE_HDR_HOOK} [AND]
cond %{HEADER:All-Cache} =""
    set-header All-Cache "%{CACHE}"
else
    set-header All-Cache "%{HEADER:All-Cache} %{CACHE}"
