two binaries with different libraries

Hi,

I have two applications (in different directories) in the
configure tree.  They need to be linked with a different set of
libraries.  What is the best way to proceed:

- using autoconf, I link the binaries with all libraries, even
  though that is overkill.

- I use *_LDADD.  In that case, as far as I know, I cannot check
  for the libraries in the configuration anymore.  Is it sensible
  to add AC_SUBST(program_LDADD) in configure.ac?

Thanks,

Frederik Fouvry