Well, I have found a solution which is not the most professionnal one,
but it works.

I use the Sendkeys function . Using a French release of outlook, the
Senkeys "letters" must be most probably changed.

Sub addSpamAdress() ' ajoute toutes les adresses des span à la liste
d'expéditeur indésirables
On Error Resume Next

Dim olItem As Mailitem
Dim objInbox As MAPIFolder
Dim oSelection
Dim arc As Outlook.MAPIFolder
Dim junkMailAddress As String

Set objNS = Application.GetNamespace("MAPI")
Set objInbox = objNS.GetDefaultFolder(olFolderJunk)
Set oSelection = objInbox.Items


For I = 1 To oSelection.Count
Set olItem = oSelection.Item(I)
If oSelection.Count 0 Then ' si il ya des mails
junkMailAddress = olItem.SenderEmailAddress
If junkMailAddress "" Then
' *******************************
SendKeys "%SSB" ' here the changes to do
' *******************************
End If
End If
Next
End Sub

Spectre a émis l'idée suivante :
Hi,

Even if spammers use often a new address for each spam they send, it is not
always the case.

Hence, I am looking for a function which could add on one click all the email
addresses of the spams beeing in the unsollicited email folder (a translation
from French for "courrier indésirable")! to the list of unsollicited mail
addresses.
I have tried to do it myself but I have been unable to find the name of this
list.

Thanks