There are not always control characters; in fact, usually there would not
be.
What you are looking for is the Unicode Bidi algorithm:
http://www.unicode.org/reports/tr9/
It describes the behavior here.

Signature
MichKa [Microsoft]
NLS Collation/Locale/Keyboard Technical Lead
Globalization Infrastructure, Fonts, and Tools
Blog: http://blogs.msdn.com/michkap
This posting is provided "AS IS" with
no warranties, and confers no rights.
> I have begun to work with Hebrew words interspersed amongst English text in
> Word 2002 Documents.
[quoted text clipped - 12 lines]
>
> Andrew
AndrewK - 09 Mar 2005 13:53 GMT
Many thanks Michael.
It would take me about a working day to fully understand that algorithm,
time I don't have (and as I am a fellow Access programmer like you, I guess I
can learn relatively quickly).
It is a shame that Microsoft didn't see fit to offer the option to notate
their documents somehow so that the user can see when language direction
changes, as this is quite a complex area and causes problems when copying and
pasting.
Oh well.
Best Regards
Andrew
Michael \(michka\) Kaplan [MS] - 09 Mar 2005 15:11 GMT
I honestly don't see how they *could* do such a thing. If there were a way
to make Bidi easier (and I am not sure there is), I also do not think most
people would consider this to be the way.
As long as the places you copy and paste into both support Uniscribe, things
should work okay here for users, though.

Signature
MichKa [Microsoft]
NLS Collation/Locale/Keyboard Technical Lead
Globalization Infrastructure, Fonts, and Tools
Blog: http://blogs.msdn.com/michkap
This posting is provided "AS IS" with
no warranties, and confers no rights.
> Many thanks Michael.
>
[quoted text clipped - 11 lines]
> Best Regards
> Andrew