  The post-Newtonian parameter $\gamma$ resulting from a universal
scalar/matter coupling is investigated in Brans-Dicke-like Scalar-Tensor
theories where the scalar potential is assumed to be negligible. Conversely to
previous studies, we use a perfect fluid formalism in order to get the explicit
scalar-field equation. It is shown that the metric can be put in its standard
post-Newtonian form. However, it is pointed out that $1-\gamma$ could be either
positive, null or negative for finite value of $\omega_0$, depending on the
coupling function; while Scalar-Tensor theories without coupling always predict
$\gamma<1$ for finite value of $\omega_0$. Moreover, regardless the value of
$\omega_0$, the subclass of theories satisfying $\gamma=1$ and $\beta=1$
surprisingly leads to almost the same phenomenology as general relativity in
the solar system.
