3 files changed, 27 insertions, 2 deletions

diff --git a/OpenSim/Framework/General/Types/RegionInfo.cs b/OpenSim/Framework/General/Types/RegionInfo.cs
index c347918..251d7f8 100644
--- a/OpenSim/Framework/General/Types/RegionInfo.cs
+++ b/OpenSim/Framework/General/Types/RegionInfo.cs
@@ -212,7 +212,7 @@ namespace OpenSim.Framework.Types
                 
                 string internalAddress = GetString(configData, "InternalIPAddress", "0.0.0.0", "Internal IP Address for UDP client connections").ToString();
                 int internalPort = GetIPPort(configData, "InternalIPPort", "9000", "Internal IP Port for UDP client connections");
-                IPAddress internalIPAddress = Dns.GetHostByName(internalAddress).AddressList[0];
+                IPAddress internalIPAddress = Util.GetHostFromDNS(internalAddress);
                 m_internalEndPoint = new IPEndPoint(internalIPAddress, internalPort);
 
                 m_externalHostName = GetString(configData, "ExternalHostName", "127.0.0.1", "External Host Name");
diff --git a/OpenSim/Framework/General/Util.cs b/OpenSim/Framework/General/Util.cs
index 3333ced..97fe7da 100644
--- a/OpenSim/Framework/General/Util.cs
+++ b/OpenSim/Framework/General/Util.cs
@@ -27,6 +27,7 @@
 */
 using System;
 using System.Security.Cryptography;
+using System.Net;
 using System.Text;
 using libsecondlife;
 
@@ -176,6 +177,30 @@ namespace OpenSim.Framework.Utilities
 
             return output.ToString();
         }
+
+        /// <summary>
+        /// Returns a IP address from a specified DNS, favouring IPv4 addresses.
+        /// </summary>
+        /// <param name="dnsAddress">DNS Hostname</param>
+        /// <returns>An IP address, or null</returns>
+        public static IPAddress GetHostFromDNS(string dnsAddress)
+        {
+            IPAddress[] hosts = Dns.GetHostEntry(dnsAddress).AddressList;
+
+            foreach (IPAddress host in hosts)
+            {
+                if (host.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
+                {
+                    return host;
+                }
+            }
+
+            if (hosts.Length > 0)
+                return hosts[0];
+
+            return null;
+        }
+
         public Util()
         {
 
diff --git a/OpenSim/Grid/UserServer/UserManager.cs b/OpenSim/Grid/UserServer/UserManager.cs
index 74d2248..c459b93 100644
--- a/OpenSim/Grid/UserServer/UserManager.cs
+++ b/OpenSim/Grid/UserServer/UserManager.cs
@@ -60,7 +60,7 @@ namespace OpenSim.Grid.UserServer
 
             // Destination
             Console.WriteLine("CUSTOMISERESPONSE: Region X: " + SimInfo.regionLocX + "; Region Y: " + SimInfo.regionLocY);
-            response.SimAddress = Dns.GetHostByName(SimInfo.serverIP).AddressList[0].ToString();
+            response.SimAddress = Util.GetHostFromDNS(SimInfo.serverIP).ToString();
             response.SimPort = (Int32)SimInfo.serverPort;
             response.RegionX = SimInfo.regionLocX;
             response.RegionY = SimInfo.regionLocY;