Solution : https://service.sap.com/sap/support/notes/529186 (SAP Service marketplace login required)
Key words : 
individual purchase order items, purchase requisition items, purchase requisition number, correction instructions provided, 32768 global data segments, 32768 global data records, getwa_too_many_segments runtime error, ========implement subsequent note 530077, global segment, program error
Related Notes : 
       
| 555047 | GETWA_TOO_MANY_SEGMENTS in SD (for IS-AFS) | 
| 530077 | Short dump GETWA_TOO_MANY_SEGMENTS - Part 2 | 
| 524562 | GETWA_TOO_MANY_SEGMENTS in SD |