Required comparators

I would like to lobby strongly for requiring the i;ascii-casemap
comparator in any base Sieve implementation.  We've implemented
the Sieve -03 draft here, and we're using it, and we find that it's
very hard to write a reasonable script without ascii-casemap.
You wind up with too many lines that look like this:

if header ("from", "to", "cc")
    contains ("ietf-mta-filters", 
              "IETF-MTA-FILTERS", 
              "IETF-MTA-Filters", 
              "IETF-MTA-filters") { fileinto "Lists/MTA Filters";

...and then you wind up patching in yet another one when the filter
fails because someone did "IETF-mta-filters" and that's not in your
list.  As long as what appears in addresses in mail headers is case-
insensitive US ASCII, we have to have a standard, *required* comparator
that handles case-insensitive US ASCII.

Any objections to adding i;ascii-casemap, in addition to i;octet, as
a *required* comparator?

Barry Leiba, Multimedia Messaging  (leiba(_at_)watson(_dot_)ibm(_dot_)com)
http://www.research.ibm.com/people/l/leiba