How to write text vertically in RichText Control

Could you tell me how to display text vertically in RichText Control?
On Windows 95, the text can be display vertically, however, on Windows 2000, it can not.
I tried another version of Richtx32.Ocx (Ver6.0.8877), but this resulted in the same.
If possible, I would like swich between Horizontal line to Vertical line or vice versa.



private Sub Writestyle(objGetRichRTF as RichTextBox, strReSetRichRTF as string, OptIndex as Integer)

Dim lngPosition as Long
Dim strLeft as string
Dim strRight as string
Dim lngTotalMoji as Long
Dim MoziStyle as string
Dim NewMoziStyle as string

Select Case OptIndex
Case 0
MoziStyle = "vertical"
NewMoziStyle = "horzontal"
Case 1
MoziStyle = "horzontal"
NewMoziStyle = "vertical"
End Select

lngPosition = InStr(objGetRichRTF.TextRTF, MoziStyle)

If lngPosition = 0 then
lngPosition = InStr(objGetRichRTF.TextRTF, NewMoziStyle)
End If

lngTotalMoji = len(objGetRichRTF.TextRTF)
strLeft = Left(objGetRichRTF.TextRTF, lngPosition - 1)
strRight = Right(objGetRichRTF.TextRTF, lngTotalMoji - (lngPosition + 6))
strReSetRichRTF = strLeft & NewMoziStyle & strRight

End Sub

private Sub Command1_Click()
Dim strReSetRich as string

Call Writestyle(RichTextBox1, strReSetRich, 0)
RichTextBox1.TextRTF = strReSetRich
RichTextBox1.Text = strReSetRich
End Sub


private Sub Command2_Click()
Dim strReSetRich as string

Call Writestyle(RichTextBox1, strReSetRich, 1)
RichTextBox1.TextRTF = strReSetRich

End Sub