LDADD problem on Redhat 8.0 (automake 1.6.3)

[Randall Hopper]

Is this Makefile.am source valid?

  LDADD = ../dira/liba.la ../dirb/libb.la

  if WITH_MY_FEATURE
  else
  LDADD += ../dirc/libc.la
  endif

A Makefile.am in our project that contains the above works fine on automake
1.7.2-32 (SuSE 8.2) but generates an invalid Makefile on automake 1.6.3
(Redhat 8.0).

The latter Makefile has a bunch of uncommented @TRUE@ lines followed by
commented out lib names, right before LDADD which is empty.

Thanks,

Randall