How could eclipse happen on the same day in a different calendar? (45 AD)
From the documentation for your program, http://www.alcyone.de/plsv/documentation/overview.html,


  Dates are in the Julian Calendar through 4 October 1582, and then in the Gregorian Calendar, which begins on 15 October 1582. (Compute for 1582, and you will see that 1. oct to 1. nov. is short.)