starting backgroun job, when instance starts up

Hi,

having the portal service implementation from earier times in mind and

look for a way to write a backgroung job, which will be started when the CE instance is started.

Therefore each portal service implements the start() method. This possibility I miss for application or any aother kind of J2EE services.

Can you provide information how this can be done on J2EE or composite application level, because I want avoid to be in touch with the prt.

Thanks,

Jens