Change in Order of Sessions at PLDI'96

The PLDI '96 program differs from the one published in the FCRC'96 Advance Program. In particular, session S2 has been swapped with session S9 and session S4 has been swapped with session S10. This was done to advoid conflicts presenters had with the Workshop of Functional Languages in Introductory Computing (FLIC). Sorry for any inconvenience this last-minute change caused.