Keeping all autotools-related files out of top_srcdir

[Rafael Laboissiere]

I am planning to change a project of mine such that all the autotools files
will be in a directory instead of in the top_srcdir.  So far, I have
a layout like this (not all files shown):

    top_srcdir/
      src/
      doc/
      cf/
        configure.ac
        acinclude.m4

In configure.ac I use both AC_CONFIG_AUX_DIR(cf) and AC_CONFIG_MACRO_DIR(cf).
I bootstrap the project with the commands run from the top_scrdir:

    ( cd cf ; aclocal )
    ( cd cf ; autoconf -o ../configure )

Everything works as expected, but I cannot add automake support to my
package, because automake seems to need both configure.ac and aclocal.m4 at
the top_scrdir.  My question is: can I convince automake to look for the
files at cf/, but still be run from the top_scrdir?

-- 
Rafael