how to decode special symbol from xml to symbol in vb 6

hi sir,
i want decode special symbol like: " ξ "
i used genral url decoder but it not working.
Public Function URLDecode(StringToDecode As String) As String

Dim TempAns As String
Dim CurChr As Integer

CurChr = 1

Do Until CurChr - 1 = Len(StringToDecode)
Select Case Mid(StringToDecode, CurChr, 1)
Case "+"
TempAns = TempAns & " "
Case "%"
TempAns = TempAns & Chr(Val("&h" & _
Mid(StringToDecode, CurChr + 1, 2)))
CurChr = CurChr + 2
Case Else
TempAns = TempAns & Mid(StringToDecode, CurChr, 1)
End Select

CurChr = CurChr + 1
Loop

URLDecode = TempAns
End Function