Solution : https://service.sap.com/sap/support/notes/1159020 (SAP Service marketplace login required)
Key words : 
nfs setup parameter nlmis set, share /sapmnt/<sid>/global, backward release installation master, /os sap business suite 2008, sap business suite 2008 reason, original installation master dvd, /operationsnw70 -> database-specific guides, /sapmnt/<sid>/profile, sap business suite 2008, prerequisites problems discovered
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