outlook signature formatted

Hi all,
I'm used to send excel spreadsheet via outlook email, adding at the end my businees signature using the following function

Public Function GetBoiler(ByVal sFile As String) As String

    Dim fso As Object
    Dim ts As Object
    Set fso = CreateObject("Scripting.FileSystemObject")
    Set ts = fso.GetFile(sFile).OpenAsTextStream(1, -2)
    GetBoiler = ts.readall
    ts.Close
End Function

and in the routine
------------------
    SigString = "C:\Documents and Settings\" & Environ("username") & _
            "\Application Data\Microsoft\Signatures\professional.txt"

Signature = GetBoiler(SigString)

------------------

unfortunately in this way the signature is not formatted

any advise to capture the signature formatted?

thanks in advance
Michelangelo