Solution : https://service.sap.com/sap/support/notes/768537 (SAP Service marketplace login required)
Key words : 
2 massively ora-00600 [koxsihread1] occur oryou, we8dec nchar character setexport server, us7ascii nchar character set, imp file=kopm_help_hp  full=, imp file=kopm_help_aix full=, imp file=kopm_help_sun full=, wrong oracle dictionary entry, we8dec character set, prerequisitesare fullfilled perform, sysdba               ignore messages
Related Notes : 
       
| 540021 | Add. information on migrating/updating to Oracle 9.2.0: UNIX |