> > simple program that prints "Al� Mundo" but when I run it, the
> > character � doesnt appear. It prints a strange character.
>   Are you saying that your source file contains a string containing
> a hex F4, but when you print that you get something other than F4?
  I notice that hex F4 appears differently when displayed in text mode
(eg: type f.txt) or in Windows mode, for instance using Notepad.  Did
you perhaps enter a character that looks right, via a graphics mode
editor, and then look at the result by running the program in text/command
line mode?  What happens if you pipe the output to a file, then look at
that file with your editor?