Critical current densities J(c) for fields applied perpendicular to MBE prepared Ge/Pb/Ge sandwiches and bare Pb films have been obtained from magnetization measurements. The single Pb film shows smooth magnetization loops at all temperatures and a monotonous decrease of J(c) with rising temperature. The Ge/Pb/Ge sandwiches reveal peaks in the magnetization curves at lower temperatures and become smooth only in the vicinity of T(c) (congruent-to 7K). J(c)(T) for the sandwiches shows a well defined maximum at approximately 5K. As a result, the J(c) values of this sandwich are increased by a factor of 3 in the temperature range 5-7K. This different behaviour may be due to enhanced pinning at the Ge-Pb interfaces, which were studied using Atomic Force Microscopy (AFM).