You can choose anyplace to store these attachments ie you can use different content server if you want to use ie Open text
Scase and organizer is sap delivered
check here http://help.sap.com/saphelp_erp60_sp/helpdata/en/42/f273461e5132c3e10000000a1553f6/content.htm?frameset=/en/82/b6b94278560c31e10000000a1550b0/frameset.htm For more information about configuring the process object in Case Management, see the Implementation Guide (IMG) for HR Administrative Servicesunder Configuration of Forms/Processes →Process Configuration →Technical Settings → Set Up Process Object.