Verifying SMTP Addresses

I created a smtp dll that uses the winsock object to send email. This connects with Lotus Notes on the server. Is there a way to verify addresses on the Lotus Notes address book or on a specific database?

Easy with MAPI (Outlook Express / Outlook etc.):

VB Code:

MAPISession1.SignOn
With MAPIMessages1
        .SessionID = MAPISession1.SessionID
        .Compose
        .RecipAddress = “a.a&a.com”
‘ Might want to add the next line as well:
‘        .AddressResolveUI = True
        .ResolveName
        .MsgSubject = "My Subject"
        .MsgNoteText = "My body"
        .AttachmentPathName = "c:\temp\test.txt"
        .Send
End With
MAPISession1.SignOff