Try out Accent or Dagesh (or any other capable WP that
deals with Hebrew, Arabic as well as Western languages. It
works out just fine.
The notion of leading language (or reading order) is
important. Once the language "boudary" is known, all else
falls in to place. The formatting scheme -- simple push
mode -- represented in digest 113 is one way to handle
things in left-to-right reading order. Numbers and
"joiners" that become part of them are re-reversed within
the "pushed" string.
Best thing is to try one of the WPs. Seeing is believing--they work!