Solution : https://service.sap.com/sap/support/notes/813445 (SAP Service marketplace login required)
Key words : 
transaction spumg -> scanner -> main log, basis support package level lower, newly created table pools, unicode conversion solution read, support packages lower, display control tables, general information umg_pool_table, execute umg_pool_table anymore, report umg_pool_table works, terms unicode conversion
Related Notes : 
       
| 1319517 | Unicode Collection Note | 
| 969660 | 6.20/6.40 Patch Collection Installation : Unix | 
| 809001 | SAP SRM Server 5.0 SR1 ABAP Installation on UNIX | 
| 808866 | SAP ECC 5.0 SR1 ABAP Installation on UNIX | 
| 785925 | SAP Web AS 6.40 SR1 ABAP Installation on UNIX | 
| 686357 | Table pool length incorrect after Unicode conversion | 
| 551344 | Unicode Conversion Documentation | 
| 544623 | New Installation of Unicode SAP systems |