I was able to correct the problem in VBA when opening a 9.3 map with ArcMap 10. I just commented the procedure and now it works. It looks like this procedure is duplicated in the code.
'Public Property Get MPSAtlas() As UID
'Dim u As New UID
'u = "{902E43BC-CF3F-4CEB-AC30-AFE2BD8ED658}"
'Set MPSAtlas = u
'End Property