SSRS 2008 NULL Parameters
How do you pass in `null` parameters into a SQL 2008 Report? The code that interfaces with the ReportExecution & ReportService2005 web services always yields an error upon executing the `ReportExecutionService.Render()` method, after I set the parameters (not including the nullable one) via invoking the `ReportExecutionService.SetExecutionParameters()` method:

`"...This report requires a default or user-defined value for the report parameter...to run or subscribe to this report, you must provide a parameter value."`

even though that parameter is defined in the .rdl file as being `null`able, and defaulting to `null`.

Must I change my code? Change parameter options in the .rdl file?
SSRS 2008 NULL Parameters
===

How do you pass in `null` parameters into a SQL 2008 Report? The code that interfaces with the ReportExecution & ReportService2005 web services always yields an error upon executing the `ReportExecutionService.Render()` method, after I set the parameters (not including the nullable one) via invoking the `ReportExecutionService.SetExecutionParameters()` method:

`"...This report requires a default or user-defined value for the report parameter...to run or subscribe to this report, you must provide a parameter value."`

even though that parameter is defined in the .rdl file as being `null`able, and defaulting to `null`.

Must I change my code? Change parameter options in the .rdl file?