Probably through the JobQueue re-design in MW 1.21 SMW_SpecialSMWAdmin.php throws now an error:

Fatal error: Call to undefined method Job::extractBlob() in ...\SemanticMediaWiki\specials\SMWAdmin\SMW_SpecialSMWAdmin.php on line 48

Well extractBlob() didn't do much other than doing an unserialize:

if ( (string)$blob !== '' ) {
return unserialize( $blob );
} else {
return false;
}

Therefore we do it ourselves:

$blob = (string)$row->job_params !== '' ? unserialize( $row->job_params ) : false;
$refreshjob = Job::factory( $row->job_cmd, $title, $blob, $row->job_id );

Version: unspecified
Severity: normal