Well, if the characters are in the file then I can only assume that your application is doing it, so back to my original sugestion, try debugging. How HTML displays is entirely down to the browser, some are less picky than others. Have you actually examined the data in say notepad to see if the characters are there? If they are, then its your application doing it, it will not be done by magic.
Bob Ashfield Consultants Ltd Proud to be a 2009 Code Project MVP