使用ASP.NET VB将子报表数据显示到Microsoft Report Viewer控件中

I've got the main report displaying just fine. Can't get the subreport to display data. Parameters are setup and linked appropriately, but still nothing. Am I missing something obvious? Is there a bug I'm not aware of? Anyone else fighting with this? I'm using Visual Web Developer Express 2008 on a SQL Express 2005 database.I've got the main report displaying just fine.