Thanks for taking the time to perform a test or two for me.  Also,
concerning your alternative:
IPHostEntry contains a collection of IPAddress objects, so I think I'm soft
of in the same situation.  The application I'm working on needs to display
the list of ipaddresses for each hostname, so I would definitely need to
iterate through that collection..

Here is a tool I call IPLookup I wrote in .NET (console app) that should
show you how to use the IP lookup stuff...

Imports System.Net
Imports System.Net.Sockets
Imports System.Reflection.Assembly

Module modCore
   Sub Main(ByVal cmdArgs() As String)

       Dim iTotalParms As Integer = 0
       iTotalParms = (UBound(cmdArgs) + 1)

       Console.WriteLine("{0} {1}.{2}.{3} Copyright (C) 2004 Joseph N.
Stackhouse", _
       GetExecutingAssembly.GetName.Name, _
       GetExecutingAssembly.GetName().Version.Major.ToString(), _
       GetExecutingAssembly.GetName().Version.Minor.ToString(), _
       GetExecutingAssembly.GetName().Version.Build.ToString())

       Console.WriteLine()

       If (iTotalParms) <> 1 Then
           Console.WriteLine("Usage: {0} <hostname>",
GetExecutingAssembly.GetName.Name)
           End
       End If

       Dim iTotalResults As Integer = 0
       Dim sIPs() As String
       Dim sNames() As String

       Dim DNSLookup As Dns
       Dim HostLookup As Dns

       Dim IPResult As New IPHostEntry

       Try
           IPResult = DNSLookup.GetHostByName(cmdArgs(0))
       Catch ex As SocketException
           Console.WriteLine("Could not resolve [{0}]:", cmdArgs(0))
           Console.WriteLine()
           Console.WriteLine(ex.Message)
           End
       Catch ex As System.ArgumentOutOfRangeException
           Console.WriteLine("Cannot process your request as one or more
segments of the address you specified exceed the maximum length allowed")
           End
       End Try

       iTotalResults = UBound(IPResult.AddressList)

       Console.WriteLine("Found a total of {0} addresses for [{1}]:",
(iTotalResults + 1).ToString, cmdArgs(0))
       Console.WriteLine()

       ReDim sIPs(iTotalResults)
       ReDim sNames(iTotalResults)

       Dim i As Integer = 0

       Do While i <= UBound(IPResult.AddressList)
           sIPs(i) = (IPResult.AddressList(i).ToString())

           Try
               sNames(i) =
HostLookup.GetHostByAddress(sIPs(i)).HostName.ToString
           Catch ex As Sockets.SocketException
               If sNames(i) = vbNullString Then sNames(i) = "none"
           End Try

           Console.WriteLine("{0}.{1}{2}{3}({4})", (i + 1).ToString, vbTab,
sIPs(i), vbTab, sNames(i))
           i += 1
       Loop

   End Sub
End Module

Alternatively you can download it from Planet Source Code at:

http://www.pscode.com/vb/scripts/ShowCode.asp?txtCodeId=1287

-L

Hi Jay,
     So, the IPAddress type will support IPv6, but the Address property
doesn't.  To get around that you're suggesting using the
IPAddress.GetAddressBytes method?  So, in theory, I could derive from
IPAddress and include my own Address property that supports IPv6, and
everyone would be happy?

Thanks!
-Michael