Solution : https://service.sap.com/sap/support/notes/39718 (SAP Service marketplace login required)
Key words : 
profile parameter/install/os_version/bos = aixif locales, lower case upper case translation table, unix command 'locale -a' shows, version handles letter 'i', /usr/lib/nls/loc, international standardized function 'setlocale', ~general/r3server/abap/note, 3  ~general/r3server/abap/note, languages------------------------------------------- eastern european sap, language dependent text processing
Related Notes : 
       
| 178430 | toupper for non latin-1 locales fixed on AIX 4.3.3. | 
| 158774 | Incorrect case mappings in some locales | 
| 73606 | Supported Languages and Code Pages | 
| 68880 | Turkish codepage setting for 3.0F upgrade | 
| 68878 | Greek language codepage settings for 3.0F Upgrade | 
| 65723 | Additional Info: Upgrading to Japanese 30F ADABAS | 
| 65722 | Additional Info: Upgrading to Japanese 30F INFORMIX | 
| 65721 | Additional Info: Upgrading to Japanese 30F ORACLE | 
| 62178 | Device types for Japanese language | 
| 50566 | Greek Codepage Installation | 
| 50402 | Turkish Codepage Installation | 
| 50028 | Pushbuttons missing on screens | 
| 47976 | Additional Info: Upgrading to Japanese 30E ADABAS | 
| 47975 | Additional Info: Upgrading to Japanese 30E INFORMIX | 
| 47933 | Additional Info: Upgrading to Japanese 30E ORACLE | 
| 47408 | Taiwanese R/3 | 
| 45463 | Thai installation procedure | 
| 42781 | RABAX TEXTENV_... | 
| 40815 | Single or Double byte installed ? (nls_check) | 
| 39473 | locale and TCP0C | 
| 39048 | abap/locale_ctype for AIX 4.1, tr_TR | 
| 35313 | How to test character sets and codings ? |