Solution : https://service.sap.com/sap/support/notes/136071 (SAP Service marketplace login required)
Key words : 
1the attached analysis program checks, additional key words emu, prerequisites incorrect translation ratios, customizing 'define translation ratios, table fields ekko-wkurs, productive local currency changeover, local currency changeover, solution contact sap, global settings -> currencies, 1m   trl   dem    01
Related Notes : 
       
| 144866 | |
| 139301 | Euro chgeover exchge rate flds convted incorrectly | 
| 139266 | Euro chgover incor. historical exchg rates created | 
| 121626 | Euro LC changeover:important Support Packages info. |