utf8 problem in index

[Marten Lehmann]

Hello,

I have a table like this:

CREATE TABLE `places` (
   `name` varchar(256) collate utf8_unicode_ci NOT NULL,
PRIMARY KEY  (`name`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci |

Then I want to insert two values:

pjöngjang.com and
pjongjang.com

But on the second record I get this message:

DBD::mysql::st execute failed: Duplicate entry 'pjongjang' for key 1

Whats wrong with it? The character set and collation set is defined as 
utf8, so mysql should see a difference between "ö" and "o".

Regards
Marten