A differential refractometric method is used to study the temperature and composition dependence of the adsorptive properties of porous glass in 2-butoxyethanol (abbreviated C(4)E(1))/water mixtures. The surface of the adsorbent carries hydrophobic-SiO-C8H17 as well as hydrophilic-SiOH groups. The experiments are carried out close to the liquid/liquid coexistence curve in the vicinity of the lower critical point of the system. Depending on the temperature and composition of the mixtures either C(4)E(1) or water is preferentially absorbed. There exists a line along which the net adsorption vanishes. For compositions x>x(c) (x, mole fraction of C(4)E(1);x(c), critical composition) the amount of substance of adsorbed water (n) over tilde(w)(s)(T-p) per unit gram of adsorbent at temperature T-p increases with increasing values of the temperature difference (T-p-T-c) in the range 0 K<(T-p-T-c)<4 K. T-p is the temperature of phase separation of the bulk mixture in the presence of the adsorbent. Beginning at temperatures (T-p-T-c)>4 K the adsorbed amount of substance <(n)over tilde (s)(w)>(T-p) decreases. At (T-p-T9c)>8 K it reaches a value which is smaller by a factor of about 10 compared with its maximum value. This phenomenon is reminiscent of a wetting transition.