I was comparing notes for the Arabic block and noticed some new additions for which I was getting Unicode box of death (i.e. none of my fonts have that symbols).
Some of them are actually Arabic math symbols which were recently added. You can read about them in the proposal at http://std.dkuug.dk/jtc1/sc2/wg2/docs/n3086-1.pdf But of course I MUST find fonts to cover these extra symbols. Some of this can be handled by using different symbols when working with Arabic math text, but it’s good to have a reference glyph.
It looks like the latest Unicode Symbols font has the Outlined White Star (5 points, rounded corners = U+269D).
An interesting conundrum are arrows which are designated “LEFTWARDS” or “RIGHTWARDS”. If I understand the proposal correctly, it appears that the conventions for which arrow is forwards or backwards would be be reverse in Arabic, so mirroring conventions are needed when using mathematical arrows in a RTL language.
Postscript – April 16, 2009
Still hunting down Arabic fonts for some of the Unicode 5 characters, but I did find a W3C page describing Arabic mathematical typesetting.
http://www.w3.org/TR/arabic-math/. Note that the some of the code is still theoretical.