Solution : https://service.sap.com/sap/support/notes/1120294 (SAP Service marketplace login required)
Key words :
adding multiple line items selecting backend contract, symptom incorrect error message, correction instructions attached, terms vendor list, line added, program error, supplier list, enter button, supplier id, occurs due
Related Notes :
| 1106934 | SRM 6.0 SP03: Additional Notes to be applied on SRM Server |