Mixing scripts (Re: Unicode versions (Re: Criteria forexceptional characters))

[Michael Everson]

At 14:37 +0900 2006-12-24, Martin Duerst wrote:

>However, mixing Ascii and Arabic or Hebrew is disallowed both in 
>IDNs and in IRIs to avoid bidi problems.

This mixing is disallowed at what level? Why would mixing Latin and 
Greek and Cyrillic at (at least) the same level not be disallowed in 
IDNs and IRIs to avoid security problems?
-- 
Michael Everson * http://www.evertype.com