Bug#34760 Character set autodetection appears to fail
the problem is the same as reported in bug#20835,
so the fix is backport of bug#20835 patch.

Original changeset:
> revision-id: sergey.glukhov@sun.com-20081121123959-58ffhp2nitg7f40h
> parent: ramil@mysql.com-20081120100836-gct60cm67b1rui29
> committer: Sergey Glukhov <Sergey.Glukhov@sun.com>
> branch nick: mysql-5.0-bugteam
> timestamp: Fri 2008-11-21 16:39:59 +0400