Dependencies to external packages

[A.P. Horst]

Hi
I'm rather new to the autotools methodology, and am facing a problem
where I can't find a solution to.
I have made two library packages, say bar and foo, where foo is
dependent on bar. They are both setup with the autotools.
Now, I can build foo one time successfully when the build directory of
foo is completely clean, but after that it fails on dependencies to bar
with a message like:
make[2]: *** No rule to make target `..../bar_something.h
..../bar_something2.h ....' needed by 'foo.o'. Stop.
foo include only bar.h from which bar_something.h etc. are included.
The Makefile.am is like this
# Where to find BAR
BARLIBS = @barlibs@
BARINC = @barinc@
AM_LDFLAGS = ${BARLIBS}
AM_CPPFLAGS = ${BARINC}
lib_LIBRARIES = libfoo.a
libfoo_a_SOURCES = foo.c
include_HEADERS = foo.h
So far I figured it discovers bar_something.h as dependencies, which is
correct, and that this message normally means that the files are
missing. But the files are truly still there, nothing has changed
meanwhile.
I'm not sure if this is the right mailing list to post to, but I would
really appreciate any help.
thanks, Arie