Hi Christian,
Refer; https://help.sap.com/saphelp_sm71_sp08/helpdata/en/bf/5a62721652477592bf3441cc5ab6ec/content.htm
and 1129385 - Downtime Management with SAP Solution Manager: FAQ
http://wiki.scn.sap.com/wiki/display/TechOps/TechAdm_Overview
I hope, that would be clearing your other doubts too.
Divyanshu