Since it can be annoying to have Propel ignore collation of tables in MySQL >= 4.1, you must force Propel to use UTF-8 collation by running the SET NAMES UTF8 SQL query.

In order to do that, you specify a filter that executes at every request. Specify the following code in filters.yml:

myUtf8ConnectionFilter:
  class: myUtf8ConnectionFilter
  activate: on

Create a new file called myUtf8ConnectionFilter.class.php in your application's lib folder and insert the following code:

<?php
class myUtf8ConnectionFilter extends sfFilter
{
  public function execute($filterChain)
  {
    $con = Propel::getConnection();
    if ($con){
       $con->executeQuery("set names utf8");
    } else {
      throw new Exception($e);
    }
    $filterChain->execute();
  }
}
?>

The code was copied from this website - I am not asserting any authorship.