How to set utf8 in the auto-generated PHP code of flash builder 4 ?

Question

HI, PHP problem here (I think):

I've just created a Flex (Flash Builder) project with a datagrid linked to a database - the database is all utf8.

When I run the project using the auto-generated code in flex4, the non-English part comes like ????? while the English part comes fine.

The auto-generated PHP code uses mysqli. I've tried:

$this->connection->set_charset('utf8');

or

mysqli_query($this->connection,"SET NAMES utf8");

or

mysqli_set_charset($connection,"utf8");

Nothing!

any help is appreciated.