Incompatibility? "Object doesnt support this property or method"

Hi,

I'm quite new to VB. Anyway, i have a worksheet macro created from officeXP, but doesnt run on 2003. I suspect it is this subroutine, as my macro shows this "Object doesnt support this property or method" when it run this subroutine. Can anyone help? thanks.

Sub CreateSubtotal()
'
' subtotal Macro
'

'
    Cells.Select
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Clear
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Add Key:=Range("J2:J1096" _
        ), SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    With ActiveWorkbook.Worksheets("Sheet1").Sort
        .SetRange Range("A1:J1096")
        .Header = xlYes
        .MatchCase = False
        .Orientation = xlTopToBottom
        .SortMethod = xlPinYin
        .Apply
    End With
    Selection.subtotal GroupBy:=10, Function:=xlSum, TotalList:=Array(7), _
        Replace:=True, PageBreaks:=False, SummaryBelowData:=True
End Sub