* The setdate command is useful, but wouldn't it be even more useful
if there was a command that extracts comparable time/date variables
from Date: headers? To handled obs-zone's timezones. E.g.,
consider if I want to sort messages sent (Date:) between 01 am and
04 am (in the senders timezone) into a folder INBOX.rants.
This would also make it easier for script writers to do more robust
time-based filtering based on Date:, since the server could also
contain functions for handling non-conforming but easily guessable
times, if they want to support that.
Looking only at the posts to this list shows people are still using
obs-zone, and if people on this list uses such MUAs, chances are
rather high that many people in the real world also does.
* A security consideration is that people should be aware that RFC
2047 encoded-word, IDNA etc potentially encode information that the
script wants to trigger on. This should have been in RFC 3028, but
as variables makes it even more likely that people will try to use
sieve scripts to filter for virus etc it might be useful to mention
it. Compare the sieve-body draft:
Filters relying on string matches in the raw body of an e-mail
message may be more general than intended. Text matches are no
replacement for a virus or spam filtering system.
* The examples in Section 3.1 and 4.1.1 should be terminated with
semi-colons to be complete Sieve commands.
* I feel variable variable names (e.g., ${foo-${bar}-baz}) would be
useful, but I can't come up with a good example why it is really
required so I'm just mentioning it if someone else can come up with
a illustrative example.