Has anyone worked with retrieving return values from Oracle stored procedures using ODBCDirect within Access 97? I'm running into some difficulty. Here's a partial code sample.

================================================================================
' The first 2 parms are return values. Other input parameters are passed,
' but not really relevant to this example.
strSQL = "{call InitializeSession(?,?, ...) }

' Create a query definition within the Oracle connection
Set qryInitializeSession = gcnnOracle.CreateQueryDef("qryInitializeSession", "")

' Specify parameters and execute the call
With qryInitializeSession
.Prepare = dbQUnprepare
.SQL = strSQL
.Parameters(0).Direction = dbParamReturnValue
.Parameters(1).Direction = dbParamReturnValue
...

' Now execute the call
.Execute

End With
================================================================================

The problem that I'm running into is this:
From everything I've read, after I create the QueryDef using ODBCDirect, ODBCDirect should create a Parameter object within the QueryDef's Parameters collection for each of the '?' placeholders in the call statement. However, that's not happening. When I try to set the Direction property of the first parameter, the code fails with the error "Object not found in collection."

I am admittedly new to using ODBCDirect so I'm not sure if the problem is that my ODBC driver does not support the capability or if I'm simply not understanding something. Does anyone have any idea what I'm doing wrong?

John