Unicode conversion issue in vertica 6.1.3

Hi, We have upgraded our Vertica database from version 6.0.1 to 6.1.3 in our non-production environment.After the upgrade when read the data from the database using our datastage jobs, we are getting a warning "Reading the WCHAR database column into a CHAR column can cause data loss or corruption due to character set conversions". It was working perfectly with the version 6.0.1. Is there any change in the unicode encoding in version 6.1.3 which is different from 6.0.1? It is also creating issues in the ETL change data capture. CDC is not happening properly when we reads from a file and compare with the data in vertica.