what is the real problem?

Here I attempt to define the problems that IMAA needs to solve from a 
user's perspective:

1. Users need to have email addresses that are easy to remember and can 
be reliably transcribed from memory.  That's the reason we like to use 
people's names in email addresses - because it makes them easy to 
remember.  ASCII addresses are not adequate because the ASCII 
repertoire is not sufficient to express people's names in most of the 
world's languages.

2. Users need to have email addresses that can easily be transcribed 
from written or printed form, so they can be copied from business 
cards, handwriting on paper, etc.
ASCII addresses do not always suffice because these characters may be 
difficult to generate on the keyboards that are commonly in use in some 
parts of the world, and because people unused to generating Latin 
characters on their keyboards can easily confuse Latin characters with 
similar characters in Greek, Cyrillic, or other alphabets.

3. Users need to have email addresses that can be transcribed from 
sounds - e.g. read over a telephone.  This is harder in some languages 
than in others, but even in most languages where this works, ASCII is 
not adequate because people may not know or recognize the names of 
Latin or special characters (even if they could type them).

So, given a suitable input device, a user who is skilled in a language 
and a writing system for that language should be able to:

a. With a high probability of success, correctly transcribe an email 
address that uses a person's name and a well-known domain string from 
that language and writing system,

b. With a high probability of success, correctly transcribe an email 
address from that language and writing system that is written or 
printed on paper,

c. With a high probability of success, correctly transcribe an email 
address from sounds spoken over the telephone by another user with 
adequate skills in that language, approximately to the extent that 
those users could successfully transcribe the same address over the 
telephone onto paper

Other constraints:

4. IMAs must have a low probability of causing operational failures 
with existing mail software - MTAs, MUAs, mailing lists, automatic 
responders, etc. - and other software which uses email addresses 
(directories, address books, security protocols, etc.).

5. All ordinary mail functions - replies, forwarding, resending, 
mailing lists, must continue to work in the presence of any mixture of 
IMA-capable software and legacy software.

6. Users need to be able to transcribe addresses that they receive in 
email, whether in message headers or in a message body, and whether or 
not their software supports the extensions that enable IMAs, and 
whether or not the recipient knows the language and script in which the 
sender normally writes his name and email address.  This is separate 
from the need to reply to messages or store received addresses in an 
address book.

(Note: #6 directly implies the need to support multiple versions of a 
sender address, in order to provide a recipient with an address that he 
can transcribe.)

Keith