Yes, unlike the IMAP SEARCH command the Sieve comparators have strict semantics. I believe it's possible to implement the Sieve comparators and Cyrus's current SEARCH comparator with a single table. The table would transcode into UTF-8 (fully decomposed) and the SEARCH comparator could do the modifications needed.different comparators would require different tables, I think. The table Cyrus usually uses isn't suitable for i;ascii-casemap since space isn't significant, but transcoding to UTF-8 and doing a dumb comparison is all that's required, a big improvement on what Cyrus is doing now, and not hard to implement.
Larry
