Testing plugin->dependencies on moodle 2.2.

My REGEXP question type version.php has these dependencies:

$plugin->dependencies = array(

    'qbehaviour_regexpadaptivewithhelp'   => 2012010100,

    'qbehaviour_regexpadaptivewithhelpnopenalty'  => 2012010100,

);

My regexpadaptivewithhelpnopenalty behaviour has this dependency:

$plugin->dependencies = array(

    'qbehaviour_regexpadaptivewithhelp' => 2012010100

);

If I install the REGEXP question type without installing any of the 2 required behaviours, on the plugins check page, in the REQUIRED column, I get a "normal" notice for the 2 missing behaviours.

Then, if I install only the regexpadaptivewithhelpnopenalty behaviour, I get 2 notices of missing regexpadaptivewithhelp behaviour. This is normal.

However, this scenario throws a PHP notice error:

Notice: Trying to get property of non-object in moodle\admin\renderer.php on line 601

Explanation:
the condition in line 601 should not be tested if $ok is false.