ProgressDialogShow freezes Input

Sub Globals
    Dim et As EditText
End Sub

Sub Activity_Create(FirstTime As Boolean)
    et.Initialize("")
    Activity.AddView(et, 0, 100dip, 200dip, 50dip)
End Sub

Sub Activity_Click
    ProgressDialogShow("...")
End Sub

Sub Activity_Create(FirstTime As Boolean)
   Dim request As HttpRequest
    Dim p1black, p3black, ... As Bitmap

   If FirstTime Then
   ... 'Some initializing here    
    End If
      
   p1black = LoadBitmap(File.DirAssets, "bSearch.png")
   p3black = LoadBitmap(File.DirAssets, "bSign-Down.png")
        ... 'Some more Stuff like that
    
   Activity.LoadLayout("main")
   
   TabHost1.AddTabWithIcon("Suche", p1black, p1white, "pSuchen")
   TabHost1.AddTabWithIcon("Downloads", p3black, p3white, "pDownloads")
         ... 'And so on

   request.InitializeGet("XXXX") 'Just to hide my Webservices :D
   
   If hcRev.Execute(request, 1) = False Then Return
   'ProgressDialogShow2("Initialisiere. Bitte warten...", False)

Sub hcRev_ResponseSuccess (Response As HttpResponse, TaskId As Int)
   Dim ergebnis() As String
   
   ergebnis = Regex.Split(":",Response.GetString("UTF8"))
        ... 'Initializing some Strings I need
   
        ProgressDialogHide
End Sub