column collation

Hi,
I am using C++ to develop an application to support SQL Server 2005. I have
a problem whant I use SQLColAttribute function. It only returns "Collation
Name", instead of the real column's collation name. Does any body has any
idea?
Here it is my code:
retcode = SQLColAttribute(handleSTMT,i +1,
SQL_CA_SS_COLUMN_COLLATION ,
columnCollation,
256, &nameLength, &valueInInt);
Thanks for you help.
--Lijie
I believe is not supported in SQLColAttribute