The characteristics of object-oriented software affect type and relevance of faults. In particular, the state of the objects may cause faults that cannot be easily revealed with traditional testing techniques. This paper proposes a new technique for interclass testing, that is, the problem of deriving test cases for suitably exercising interactions among clusters of classes. The proposed technique uses data-flow analysis for deriving a suitable set of test case specifications for interclass testing. The paper then shows how to automatically generate feasible test cases that satisfy the derived specifications using symbolic execution and automated deduction. Finally, the paper demonstrates the effectiveness of the proposed technique by deriving test cases for a microscope controller developed for the European Space Laboratory of the Columbus Orbital Facility.