Re: SPF is harmful. Adopt it.

M> Via SMTP, the sender dictates when he needs a few seconds of
M> connectivity to send the message.  In case of IM2000, the 
M> recipent wants to dictate when network connectivity is needed 
M> to the sender's mailstore.

In the SMTP-based Internet mail system, the recipient either has to be
permanently connected, and run his/her own SMTP Relay server; or relies upon
good network connectivity to some "out on Internet" entity (such as Hotmail,
or a POP3 server) just as in the IM2000 Internet mail case.

M> The point is not whether network connectivity is available, 
M> but _when_ its availability needed to get the actual message.

In the case of IM2000 it is needed at the point when the recipient decides to
fetch the message, which is a logical place for it.  This isn't a concept that
is hard for people to come to grips with, nor is it the fact that connectivity
may be unavailable something that they will find unusual.  People have already
come to grips with this sort of thing with respect to browsing the web. 
Indeed, as I keep hinting, the millions of
Hotmail/Yahoo!Mail/POP3/IMAP/whatever users Out There also seem to have come
to grips with it when reading mail.

M> I am not sure IM2000 would pay off for my mother: she lives 
M> in Hungary where you pay for telephone usage by the minute.

I've already addressed this in response to your other message.  It's based
upon the erroneous assumption that your mother will need to be on-line as she
reads a list of notifications and decides which messages in the list she will
actually fetch or refuse.

M> Presently, she just dials in for maybe a minute to download all 
M> her messages from her ISP.

And with IM2000 all that she has to do is behave as she would have to behave
if reading Usenet off-line.  The "Go on-line once briefly to fetch the list of
stuff that is available, and then go on-line again once you have selected what
stuff to fetch and what stuff to refuse." paradigm is neither hard nor without
_several_ precedents.