there is some nasty way to get around this.
first you have to create a hot key which enables the insert comment action for you.
then you have to create the insert comment macro.
and at last you have to create a macro when the selection changes the sheet is set to protection again like this.
place these macros in the ThisWorkbook section:
Private Sub Workbook_Open()
Application.OnKey "{F12}", "InsertComment"
End Sub
Private Sub Workbook_Close()
Application.OnKey "{F12}"
End Sub
the next macro goes into a new module:
Sub InsertComment()
ActiveSheet.Unprotect
Selection.AddComment
'ActiveSheet.Protect
End Sub
the last macro make it possible to edit the workbook and then when another cell is selected it is set to protected again. it should be placed in the workbook where comments insertion is allowed.
Private Sub Worksheet_SelectionChange(ByVal Target As Excel.Range)
ActiveSheet.Protect
End Sub
cheers!
Jeroen