Solution : https://service.sap.com/sap/support/notes/1593844 (SAP Service marketplace login required)
Key words :
/sp-stacks -> sp stack maintenance schedule, collaboration room takes longer, sp stack schedule, sp patch level, relevant portal groups, room members, symptom creating, large amount, prerequisites reason, affected releases
Related Notes :
| 1455760 | KMC in SAP NetWeaver 7.0 EHP2 SPS05 |