A colleague was tasked to rebuild a program was developed on top of an ancient version of IBM Lotus Notes.
I've been searching with her for programs to export the data from the NSF file that also support Arabic. We didn't know which encoding the NSF was using either. She contacted the authors and companies of many programs and all said that it depends on the computer you're executing the program on. Well, we tested them on computers which already have Arabic installed and everything set properly but still failed to export the data properly.
Eventually, I thought of trying to export the data from the latest Lotus Notes software available (8.5 stable), and it worked! I had to open the view which contained the listed data and then export and make sure I selected UTF-8 or Unicode (No clue what's the difference!).
Lotus Notes 8.5 allows to export in Comma Separated Value format (CSV), Structured Text, tabular Format and ASCII. To obtain full information on each record I had to export the data in Structured Text format. CSV only exported the visible data in the current view; if you double click a record you'd get the rest of the data in the view.
Structured Text for now, unless I find a way to export the full data in CSV. (I'm feeling lazy now that the data is exported in Structured Text already .. it requires some parsing but its there!)