Description:
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Hi, I've some expression in database in UTF8.
When i try to use the htmlentities functions

ex : htmlentities("zoo...", ENT_QUOTES, "UTF-8");

the script returns sometimes nothing.


PS : I've tested on a PHP 5.1.2-1.dotdeb.2 (and i can't upgrade at work)... i will try at home with a PHP 5.1.4 version

Reproduce code:
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// works always
$str = " ";
echo htmlentities(html_entity_decode ("ζωολογικός".$str."κήπος/πάρκο", ENT_QUOTES, "UTF-8"), ENT_QUOTES, "UTF-8");

// works sometimes
$str = " ";
echo htmlentities(html_entity_decode ("ζωολογικός".$str."κήπος/πάρκο", ENT_QUOTES, "UTF-8"), ENT_QUOTES, "UTF-8");