Solution : https://service.sap.com/sap/support/notes/827999 (SAP Service marketplace login required)
Key words : 
code page/language vector reason, code page/language vector maintained, error => rfc ====> rscplangcplistgetcptry failed, completely maintained, trfc communication, unicode system, -unicode system, system ignores, transaction sm59, triggers terminations
Related Notes : 
       
| 1319517 | Unicode Collection Note | 
| 828000 | Rfc Patch Collection 11 2005 | 
| 814707 | Troubleshooting for RFC connections Unicode/non-Unicode |