How do I add a new condition in Rules 2? I can't get my new Rules' condition to work.

I wrote the (simple) code below in includes/MYMODULE.rules.inc, and nothing appears in the condition list.

/**
 * Implementation of hook_rules_condition_info().
 */
function MYMODULE_rules_condition_info() {
    return array(
        'MYMODULE_rules_condition_MYCONDITION' =&gt; array(
            'label' =&gt; t('My label'),
            'group' =&gt; 'My very own group',
        )
    );
}

/**
 * Condition
 */
function MYMODULE_rules_condition_MYCONDITION() {
    // logic
    return TRUE;
}


I have already tried to flush the Drupal cache (as it seems to me that Rules uses a cache system).
Read Rules 2.x / Drupal 7; I think you can find what you want, there.