here is the VB version of it.  sorry for the long formatting, I just copied and pasted the code from VS 2005.

Dim rpt As ReportDocument = New ReportDocument

Dim rSections As Sections
Dim rSection As Section
Dim sReportObjects As ReportObjects
Dim sReportObject As ReportObject
Dim subReportObject As SubreportObject
Dim subReportDoc As ReportDocument
Dim rptTxtGroup As TextObject

 
rSections = rpt.ReportDefinition.Sections

For Each rSection In rSections
     sReportObjects = rSection.ReportObjects
     For Each sReportObject In sReportObjects
          If sReportObject.Kind = ReportObjectKind.SubreportObject Then
               subReportObject = sReportObject
               subReportDoc = subReportObject.OpenSubreport(subReportObject.SubreportName) 
               rptTxtGroup = subReportDoc.ReportDefinition.ReportObjects.Item("Text3")
               rptTxtGroup.Text = "Test"
          End If
     Next
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