Auto Date Stamp - Disabled undo button

Hi Folks

I found a great little piece of code which does exactly what I want in that if a cell in colum C to M is amended, it automatically updates column B with the date it was changed.

Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("C:M")) Is Nothing Then
Cells(Target.Row, 2) = Date
End If
End Sub

Problem is that I have noticed that any changes within columns C to M loses the undo history. cells outside of those paramters (i.e. columns N onwards) keep the history as long as nothing is changed in C to M. Is there a way of keeping the undo history by amending or adding to the above code?

Cheers