Using Informix Client SDK I get this error ( The parameter data type of DBNull is invalid )

We have the following environment

..Net Framework 2.0
- Informix Client SDK 2.90 TC6
- Informix 9.40 FC8

The following error started appearing after we upgraded to TC6. It
never happened in TC4/TC5.


System.ArgumentException: The parameter data type of DBNull is
invalid..
at IBM.Data.Informix.TypeMap.FromSystemType(Type dataType, Int32
iLength)
at IBM.Data.Informix.IfxParameter.GetParameterValue()
at IBM.Data.Informix.IfxParameter.Bind(IntPtr stmt, IfxCommand
parent, Int16 ordinal, CNativeBuffer buffer, CNativeBuffer intbuffer)
at IBM.Data.Informix.IfxCommand.ExecuteReaderObject(CommandBehavior
behavior, String method)
at IBM.Data.Informix.IfxCommand.ExecuteReader(CommandBehavior
behavior)
at
IBM.Data.Informix.IfxCommand.System.Data.IDbCommand.ExecuteReader()

Please help

.

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