I am not sure which ‘Task Manager’ you are referring to as different ones would act differently, so I am basing my answer on the action when the user goes to Settings–>manage Applications and–> force stops the app the way android has given him.
Assuming that your service is running as part of the process and if the user force-stops your process, you are prevented from ever running the service again until the user manually launches you.This is especially valid from 3.0 and above version ( check for yours). It also seems logical when you think that there is an app which keeps a service started all the time and is annoying the user in some way. So when the user orders a hit ( 🙂 force-stops) on the app, it should not restart the service to continue bugging the user.
For instance, Imagine what would happen if you could create apps which just ate at your processor time by holding a wake lock, and you couldn’t kill them. This would be horrible and a huge security disaster.
So, you will not be able to restart your service by any means until the user launches one of your activities.
Also you cannot disable the force-stop button AFAIK. You should take the viewpoint that nothing on the device is yours to control besides your app and (to a limited extent) the resources to which you’re granted access.
Finnally, even the gtalk app will bend to your will if you desire to force stop. It will start only when you use Gtalk or other apps which use the gtalk service such as PUSH Gmail ( for phones where gtalk isnt a part of firmware). Also take a look at Android C2DM here: