Auto Correct Load Generates Only Insert Statement

We updated SAP BO DS from XI 3.2 to 4.1.

Now auto correct load is not working as expected for some data flows.  It does not update data, only insert it.

Before upgrading, data flows generate sql like: IF EXISTS (SELECT .... FROM Table WHERE KeyColumn = KeyColumnValue) UPDATE .... ELSE INSERT ... .

Now, it only generates insert statement.  The interesting thing is, auto correct load works as expected in some data flows.

Both source and target databases are SQL Server 2008 R2.

Target table settings: Auto Correct Load : Yes, Use input keys : Yes, Allow Merge or Upsert: Yes

Is there any other setting that i missed.

Thanks for your help