Solution : https://service.sap.com/sap/support/notes/914168 (SAP Service marketplace login required)
Key words : 
odm order document type pfrq, activated1 etp111 exit code, structure /1om/odm_pfro_str_[client]-, table /1om/pfrqpfro[client], table /1ot/pfrqpfro[client], order document type, order document management, /1om/odm_pfro_str_[client], /1om/pfrqpfro[client], /1ot/pfrqpfro[client]
Related Notes : 
       
| 1292071 | Add. info. on upgrading to SAP SCM 7.0 SR1 ABAP | 
| 1156970 | Add. info. on upgrading to SAP SCM 7.0 ABAP | 
| 1108700 | Add. info. on upgrading to SAP SCM 5.0 SR3 ABAP | 
| 1010762 | Add. info. on upgrading to SAP SCM 5.1 ABAP | 
| 961512 | Add. info. on upgrading to SAP SCM 5.0 SR2 ABAP | 
| 925240 | Add. Info. on upgrading to SAP SCM 5.0 SR1 ABAP | 
| 826093 | Add. info. on upgrading to SAP SCM 5.0 ABAP |