On Tue, Feb 21, 2017 at 4:50 PM, Andrei Ivanov <andrei.ivanov@xxxxxxxxx> wrote: >>> >>> Header set Client-SAN "%{PeerExtList('2.5.29.17')}s" The syntax may be rather: Header set Client-SAN "expr=%{PeerExtList:2.5.29.17}" Does it work better?