ADO Openschema to different datasources

Can anybody help me with this problem please???

I set up 3 datasources (ds1,ds2,ds3) by the Sybase OLE DB Provider Cofiguration Manager.
Those 3 datasources are associated with different databases(db1,db2,db3) respectively.

I create an ADO connection object pointing to the ds2. I am able to open the connection and access the right data in the database. However, when I try to use this connection object to retrieve meta-data by using
Cn.Openschema(adadSchemaTables), it returns tables info in the ds1 (which is the first item in the datasouce list in Sybase Configuration manager). I try to open a connection to ds3, the openschema still returns me data in ds1. I even specify the initial catalog in the connection string explicitly, still not working. (Actually, not matter what I specify in the connection string, after the connection is opened, I debug.print the connection string, it always says the initial catalog is db1).