When changing the Task Server port bindings on the Settings page (Settings | Notification Server | Site Server Settings, then expand on the left: Site Management\Settings\Task Service\Settings and select Task Service Settings), the new ports don't bind, leaving either some unbound ports, or the product bound to the wrong / old ports.
There are a few possibilities for why this may be happening:
There are some work-arounds we can apply to this situation, and Development is researching why the changes are not automatic.
To resolve the first scenario, make sure that "Automatically restart services when configuration changes" is checked on the Task Service Settings Page and be sure to save your changes. If you would not like have the services automatically restart, then the three listed services (Object Host Service, Client Task Dataloader, WWW Publishing) will need to be restarted manually.
To resolve scenarios 2 and 3, using the following steps should change the ports:
To verify the bound ports have changed, open a command prompt and run 'netstat -an' to display bound ports.
Notification Server 7.0, SP1, SP2