Solution : https://service.sap.com/sap/support/notes/952388 (SAP Service marketplace login required)
Key words : 
sap processes continuously hang, crocllnk script ran correctly, system generates short dumps, obsolete oracle 9i client, -task communication protocol errorora-03113, oracle client software version 9, operating systemcore dumps, pure application servers, oracle server release, software version 9
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