For some reason, the columns are related to two language codes: 936 and 1252. Still do not know how this happens. Win 7's locale is English. The SQL Server server and database collations are Latin. The language code for all of the DB destinations in the solution is 1252. Do not know where 936 (Microsoft's character encoding for simplified Chinese) comes from?
But anyway, if I change the OLE DB destination codepage to 936. The package works.
