[XeTeX] opentype arabic font rendering in mac osx (snow leopard and lion)

[Arthur Reutenauer]

> A supplementary question : how does the PDF appear when
> viewed in Acrobat Reader or in Adobe Acrobat ?  From a
> purely personal perspective, I would always check the
> rendering in those before assuming that the PDF was at
> fault -- it may well be simply an incompatibility with
> the viewer(s).

  In this case, this is a known problem with Adobe Arabic: its glyph
outlines use 2048 units per em, instead of 1000 (more standard value for
CFF-based OpenType fonts, but by no means mandatory).  Adobe Reader
doesn't handle that correctly and display the glyphs at (a little bit
over) double the size they should have.

	Arthur