Dim objMenu As CommandBar
Dim objItem As CommandBarControl
Dim objComment As CommandBarControl
Dim lngPos As Long

' Retrieve shortcut menu
Set objMenu = CommandBars("Cell")

' Create My Own Macro item
If Not objComment Is Nothing Then
   ' Get position of Insert Comment item
   Set objComment = objMenu.Controls("Insert Co&mment")
   lngPos = objComment.Index

   ' Add menu item
   Set objItem = objMenu.Controls.Add _
                          (msoControlButton, 1, , lngPos,True)   
   objItem.OnAction = "MyOwnMacro"
   objItem.Caption = "M&y Own Macro"
End If