kdelibs3 build fails on Snow Leopard

[Richard L. Hamilton]

:info:build *** Creating aclocal.m4
:info:build aclocal: warning: autoconf input should be named 'configure.ac', not 'configure.in'
:info:build acinclude.m4:3724: warning: the serial number must appear before any macro definition
:info:build acinclude.m4:3769: warning: the serial number must appear before any macro definition
:info:build acinclude.m4:3814: warning: the serial number must appear before any macro definition
:info:build acinclude.m4:6007: warning: the serial number must appear before any macro definition
:info:build acinclude.m4:12474: warning: the serial number must appear before any macro definition
:info:build configure.in:24: error: Autoconf version 2.65 or higher is required
:info:build /opt/local/share/aclocal-1.13/init.m4:23: AM_INIT_AUTOMAKE is expanded from...
:info:build configure.in:24: the top level


However,
/opt/local/bin/autoconf --version
autoconf (GNU Autoconf) 2.69

OTOH, the Apple binary in /usr/bin/autoconf is 2.61.  So maybe it's using the wrong one?