Dspace 6.3 schema validator returned: Could not instantiate id generator

[Jeffrey Chan]

Our company required us to use Dspace 6.3 with mysql. Although I know you are not supporting Mysql, can I ask question that I encounter an issue. At first dspace 6.3 runs normally with Oracle, then I tried to change to mysql. I can connect to mysql database(mysql 5.5), mysql-connector-java 5.1.22,  but when I tried to type "dspace create-administrator", it throws exception: Exception: The schema validator returned: Could not instantiate id generator [entity-name=org.dspace.content.MetadataSchema]

I have changed the metadata_schema entity id generator not using "sequence", I have changed to @GeneratedValue(strategy = GenerationType.IDENTITY). I have no idea so asking your help, thanks!!!