(ITS#4724) Case-insensitive search on unicode strings fail in 2.3.x

[katuev@dvbank.ru]

Full_Name: Konstantin Katuev
Version: 2.3.28
OS: Solaris
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (195.137.171.26)


When using unicode (russian) strings for DNs & attribute values, all sofwtare
that searches thru LDAP directory returns no results when case of letters does
not match.
If case of letters matches, everything is OK. On ASCII strings search works
fine.
Older versions (2.2.x) work good.
I've upload sample data
(ftp://ftp.openldap.org/incoming/case-unicode-test.ldiff)
and simple perl script (ftp://ftp.openldap.org/incoming/case-unicode-test.pl)
that can reproduce this behavior. Script will find 1 record when run against
2.2.x server and nothing on 2.3.x.