no .deps directory generated

[David Byron]

I'm having trouble getting a .deps directory generated when I think it
should.  As a result, I see this error:

Makefile:357: .deps/TestECVersion.Po: No such file or directory

I don't think I'm doing anything particularly complicated.

My directory structure looks like this:

agent
  config/
  testmain/
  util/
    tests/

where configure.ac lives in agent and contains:

AC_CONFIG_FILES([Makefile util/Makefile
util/tests/Makefile:config/cppunit.mk.in:util/tests/Makefile.in
testmain/Makefile])

and, Makefile.am in agent contains:

SUBDIRS = testmain util

and Makefile.am in util contains:

SUBDIRS = tests

Makefile.am in tests contains:

noinst_PROGRAMS = immOutTester threadStartTester zombie testrunner
immOutTester_SOURCES = immOutTester.cpp
threadStartTester_SOURCES = threadStartTester.cpp
zombie_SOURCES = zombie.cpp
taestrunner_SOURCES = TestECVersion.cpp

I run

agent $ autoreconf -fvi
aagent $ rm -rf build; mkdir build; cd build; ../configure
agent $ find . -name ".deps"
./util/.deps
./testmain/.deps

Note that if I change the AC_CONFIG_FILES in configure.ac to:

AC_CONFIG_FILES([Makefile util/Makefile util/tests/Makefile
testmain/Makefile])

things work fine (i.e. util/tests/.deps exists).

I'm using automake 1.10 and autoconf 2.61 on linux/bash/make 3.79.1.  Any
chance I need to upgrade make to pull this off?

I'm not sure what other info I should send to be helpful (config.log?
Makefile.am?  cppunit.mk.in?  All of it?)

Thanks for your help.

-DB