Originally Posted by orpheus2011
I thought so too, but I then tried with fonts such as Times New Roman, which work flawlessly when applied to Latin text and then fall short on the Arabic/Persian script.
It is your fonts fault. If you used Times New Roman straight out of Windows, then it would not have any arabic characters in it. The PW would than most likely fall back to a default / backup font. In Win7 at least, when you click on a font it will show in the bottom what characters it is intended for. My Times New Roman says designed for: Latin, Greek, Cyrillic, Hebrew. The only fonts I see on my Win7 that have arabic characters are: Andalus Regular, Arabic Typesetting Regular, Arial, Sakkal Majalla, Simplified Arabic, Simplified Arabic Fixed Regular, Traditional Arabic.
Maybe try one of those. I would be happy to test any, but it is impossible to find a mobi or azw3 that is in arabic and text only. Can't even find a quran - if you got one in english and arabic alternated that is text only, I'd be happy to get that (if it is free of course).