[2005] Getting current week number

[Riks]

Hi all

First of all I must apologize for brining this subject up yet again on these forums. I have searched for soluions and I also thought i found it.
However it seems to make some kind of miscalculation or something..
Here's one of the solutions I found in my search.

Public Class Form1
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MessageBox.Show(Me.GetMonthWeekNumber(Me.DateTimePicker1.Value).ToString())
 
    End Sub
 
    Private Function GetMonthWeekNumber(ByVal [date] As Date) As Integer
        Dim cal As Globalization.Calendar = Globalization.CultureInfo.CurrentCulture.Calendar
 
        Dim monthStartWeek As Integer = cal.GetWeekOfYear(New Date([date].Year, _
                                                                   [date].Month, _
                                                                   1), _
                                                          Globalization.CalendarWeekRule.FirstDay, _
                                                          DayOfWeek.Monday)
        Dim currentWeek As Integer = cal.GetWeekOfYear([date], _
                                                       Globalization.CalendarWeekRule.FirstDay, _
                                                       DayOfWeek.Monday)
 
        Dim monthWeekNumber As Integer = currentWeek - monthStartWeek + 1
 
        Return monthWeekNumber
    End Function
 
End Class

But when i compared the result with what i found on MS Outlook it didnt seem to match. Outlook, as does my program, use Monday as first day of week. But if you select the date 01.01.2006 in the DateTimePicker it will say that the weeknumber is 1. Outlook however claims it to be week #52.
(01.01.2006 is a sunday). This means that my program, using the code above, will claim that there are 53 weeks in this year..
Is there any other method I can use that will display the correct week number of a selected date?