Dear All,
I put a simple solver, written in Delphi.
Program URL: http://www.geocities.com/jimichou/sudoku/sudoku_d_solver.zip
Source URL: http://www.geocities.com/jimichou/sudoku/source/sudoku_d_source.zip
It is a very simple program, and also simple in its logic. So far, I have not got any puzzle can not be solved by it.
It can export its solving steps, and trials steps, too.