LDAP integration request - having issue with Vietnamese characters in name

Case -> 07304573

ISSUE: LDAP Doctors with Vietnamese characters in first,last,middle name are not able to login. ERROR: <exception>java.lang.Exception: IMS Error - RollbackException: The transaction has been marked for rollback (Database error: com.sybase.jdbc4.jdbc.SybSQLException: Error converting characters into server's character set. Some character(s) could not be converted. Vietnamese character can't be remove from doctor name. Reason: This AD synchronized with SAP system and the doctor name should be Vietnamese to do report and all other thing. I ask already and AD can’t remove. Insurance system check carefully if the doctor name is not in VIETNAMESE and refuse payment. All detail testing are in the attached document file. Noted: LDAP Doctors WITHOUT Vietnamese characters in first,last,middle name are able to login.