SSRS 2008: Different execution behaviour of report parameters in BIDS and Report Server

Hi,

my report has four parameters (pYear, pMonth, pCustID, pSubCustId) each getting their availabe and default values from a dataset.

When I run my report in BIDS, each parameter is populated by the queries resultset,

however when I deploy the report to the Target Server (SQL Server 2008 R2) and

execute it by using IE8, only  parameters pYear and pMonth (as dropdown box) are populated as expected, the others are blank.

I've setup Parameters pMonth, pMonth, pCustID, pSubCustId to be cascading by specify a T-SQL whereclause.

ex. for Parameter pCustID

SELECT CustID, CustName from vwCustomers where Year = @pYear and Month = @pMonth

I'm currently clueless where to look further,

so I've made sure that my Report deployment properties OverwriteDatasets, OverwriteDataSources are set to true.

Any clues on how to troubleshoot are greatly appreciated.

Thanks

Bodo