FYI, you can actually make C6.3 use the newer native clients by specifically specifying the driver in your owner string.
I used this method with older C6 projects until they could be converted. If you append this to your owner string it will work.
;Driver=SQL Server Native Client 11.0
You can determine what sql native client is installed and get the proper driver name by reading the registry.
GetReg(REG_CLASSES_ROOT,‘SQLNCLI11’)
or
GetReg(REG_CLASSES_ROOT,‘SQLNCLI10’)
I give additional details in this post: Clarion 6.3 x MSSQL server (enable MARS?)