Major changes to Unicode for Arabic & Hebrew

UAX #9, Unicode Bidirectional Algorithm, will be updated for Unicode 6.3. The Unicode BIDI algorithm is used for displaying all Arabic and Hebrew text on the web and in application programs, so any changes require careful review.

This proposed update involves a substantial extension of the Unicode Bidirectional Algorithm to allow for the implementation of isolate runs. It also introduces new Bidi_Class property values and formatting characters in support of that extension.

There are also changes to Section 3.3.4 Resolving Neutral Types to resolve paired punctuation marks as a unit. This adds a new rule N0.

See the modifications section of the proposed update for information on specific changes to sections in the document.

The proposed update is available here: http://www.unicode.org/reports/tr9/tr9-28.html