Last time I checked the actual Kindle hardware devices still do not support any RTL languages nor glyphs. But it is now supporting CJK (Chinese Japanese Korean)
Check out this site for a bunch of test mobis you can used to see which glyphs a Kindle device actually displays vs. which it displays the [?] "Huh?" glyph for.
http://freekindlebooks.org/Unicode/unicode.html
None of the Kindle emulator software seems to accurately represent what glyphs are actually on the devices.