Well, so what? It's taking current at a lower voltage because it's in a discharged state. As the concentration of Pb-->PbO2 and PbSO4-->Pb rises, the cell potential also rises. (In fact it's up to 13.74V already.) When all surfaces are fully charged, the voltage levels off somewhere around there (when under some degree of charge, because again, overpotential). I'm going to float it at 14.2 for a while (preferably 12-24 hr, not sure if I'll get that much time on it tonight) to ensure a full charge (desulfation, to the extent that it can be performed at all).
Tim