Patrick Chew wrote:

> [...]
> I would agree that rpesence of any of the extended letters, e.g. peh,
> cheh, geh, etc., would give any non-Arab script away as beign
> non-Arabic.

Most of these letters (especially p, v, ch and zh) are used in Arabic as
well, to transliterate foreign words. It is not likely to see them in poor
typography (such as daily newspapers) but they are not so uncommon on, e.g.,
a book about history or geography.

Of course, their rate of occurency would be dramatically different in Arabic
vs. Persian: more or less the same difference of the occurrences of "ç" in
English vs. French.

Also the "Persian" form of final kaaf and yaa can be seen in Arabic: they
are quite common especially in the Maghrib countries.

--
Cingar