I saw that answer. I also downloaded the files which ISE managed to "run". In that modified project, the classes were converted to version 20 point something and my offending classes were removed. So, of course it ran with no errors. Am I to understand that no one there actually ran my files or tried to duplicate my error? What is odd, I used these same classes in a library that produces SHA digests and it seems to work fine. "Adding a feature to such a class usually involves changes to the compiler. This explains why not everything works as expected." Okay, but is it not worth checking to see if that is the case? Why does it work for most of the tests but not that simple one (which is almost identical to others which work just fine? Give me one last answer and I will drop this. jjj