If you run a job manually with "Do now" from the Tools->Crontrol screen in WP2.7, you'll most likely get a "missing argument 1 for spawn_cron()" error. In order to fix this, edit the "run_cron" function in wp-crontrol.php file.
You need to add $local_time to the spawn_cron call.
function run_cron($hookname, $sig) {
// Add this:
$local_time = time();
//
$crons = _get_cron_array();
foreach( $crons as $time=>$cron ) {
if( isset( $cron[$hookname][$sig] ) ) {
$args = $cron[$hookname][$sig]['args'];
wp_schedule_single_event(time()-1, $hookname, $args);
// Change this:
spawn_cron($local_time);
//
return true;
}
}
return false;
}
This will make this function call spawn_cron() correctly allow the plug-in to work again.