Thanks. I found that https://lists.gnu.org/archive/html/automake/2007-01/msg00071.html, https://lists.gnu.org/archive/html/automake/2007-01/msg00075.html have described this workaround
On Fri, Jun 3, 2016 at 8:36 AM, ellie timoney via Cyrus-devel < cyrus-devel@lists.andrew.cmu.edu> wrote: > On Thu, Jun 2, 2016, at 02:48 AM, qyb via Cyrus-devel wrote: > > ./configure --help says "--sysconfdir=DIR read-only single-machine > data [PREFIX/etc]" > > "sysconfdir" should set to "{prefix}/etc" in Makefile, but it set to > "/etc". > > > The choice to default it to "/etc" rather than "${prefix}/etc" is > deliberate, for historical compatibility. But the standard --sysconfdir > option is honoured if you wish to override it. (Commit c185645, November > 2003.) > > The help text for --sysconfdir is provided by autotools, not by us. > "[PREFIX/etc]" is wrong for our case, but I don't know of a way to > override it with our own text. Does anyone else? >