Excel doesn't use UTF8 to open CSV files. Thats a known problem. The actual encoding used depends on the locale settings of Microsoft Windows. With a German lcoale for example Excel would open a CSV file with CP1252.
You could create an Excel file containing some persian characters and save it as an CSV file. Then write a small Java program to read this file and test some common encodings. Thats the way I used to figure out the correct encoding for German umlauts in CSV files.
