Creating Connection Managers & You may be unable to execute SQL Server 2005 Integration Services packages that contain script tasks or script components & 64 bit

Setting the Project Properties to Run64BitRuntime = false resolves this.... and while scheduling you'll need to use the x86 version of dtexec.

Both versions of the provider have the same ID. To specify whether the Integration Services runtime uses an available 64-bit version of the provider, you set the Run64BitRuntime property of the Integration Services project. If the Run64BitRuntime property is set to true, the runtime finds and uses the 64-bit provider; if Run64BitRuntime is false, the runtime finds and uses the 32-bit provider. For more information about properties you can set on Integration Services projects, see Integration Services Considerations on 64-bit Computers and Integration Services in Business Intelligence Development Studio.

Creating Connection Managers