How to disable auto-correction for excel vba

Question

I've an issue when coding in excel-vba editor. Some classes beginning with uppercase have become lowercase for their first letter. For example:

• Range -> range
• ThemeColor -> themeColor

Here's the example code

Sub SetAltColor(source As range, themeColor As XlThemeColor, percent0 As Double, percent1 As Double)
'
' Set alternative color for rows
'
Dim i As Integer
With source
    .Font.themeColor = themeColor
    For i = 1 To source.Columns.Count
        With .Cells(1, i).Font
            If (i Mod 2 = 0) Then
                .TintAndShade = percent0
            Else
                .TintAndShade = percent1
            End If
        End With
    Next
End With
End Sub

As you can see, the 1st parameter show range and at line 7, you can see .Font.themeColor as well

excel version 14.0.7151.5001 (32bit)

Can someone explains what happens and how should i fix this problem? Thanks a lot.