@stof If I've understood correctly the scenario is the following:
```
// just a "pseudo-code" fully expanded
$em->find( array(
    'assoc1' => array(
        'assoc1_1' => 'value1',
        'assoc1_2' => 'value2'
    ),
    'assoc2' => 'value3'
);

// which in reality will be mapped as
$em->find( array(
    'assoc1_1' => 'value1',
    'assoc1_2' => 'value2'
    'assoc2' => 'value3'
);
```
Similar to my original post, but ``$instance1`` will be expanded to two values. Still I don't know if this is something that should/must be supported, and if it is possibile to implement.