Solution : https://service.sap.com/sap/support/notes/584902 (SAP Service marketplace login required)
Key words :
ale message type preqch, data type char fields, user-defined fields, account assignment data, bapi_requisition_create function module, business object repository, business object bus2105, similar data types, standard table fields, bapi_requisition_change function module
Related Notes :
| 792132 | EBAN, EBKN: user-defined fields are not filled |
| 499627 | FAQ: BAPIs for purchase requisitions |
| 485557 | BAPI_REQUISITION_CREATE: 'EXTENSIONIN' customer enhancements |