Thank you kindly, MCortez, for a patch that:

This hooks up the LandManagementModule to handle the DeedParcelToGroup 
packet. Now people can start testing land assigned to and owned by groups.
Also fixes a viewer crash issue when searching for and then joining a group 
with an agent that is not already being tracked by groups server.

OpenSim/Region/CoreModules/World/Land/LandManagementModule.cs

@@ -121,7 +121,9 @@ namespace OpenSim.Region.CoreModules.World.Land
             client.OnParcelReclaim += new ParcelReclaim(handleParcelReclaim);
             client.OnParcelInfoRequest += new ParcelInfoRequest(handleParcelInfo);
             client.OnParcelDwellRequest += new ParcelDwellRequest(handleParcelDwell);
-            
+
+            client.OnParcelDeedToGroup += new ParcelDeedToGroup(handleParcelDeedToGroup);
+
             if (m_scene.Entities.ContainsKey(client.AgentId))
             {
                 SendLandUpdate((ScenePresence)m_scene.Entities[client.AgentId], true);
@@ -129,6 +131,7 @@ namespace OpenSim.Region.CoreModules.World.Land
             }
         }
 
+
         public void PostInitialise()
         {
         }
@@ -1125,6 +1128,24 @@ namespace OpenSim.Region.CoreModules.World.Land
             }
         }
 
+
+        void handleParcelDeedToGroup(int parcelLocalID, UUID groupID, IClientAPI remote_client)
+        {
+            // TODO: May want to validate that the group id is valid and that the remote client has the right to deed
+            ILandObject land;
+            lock (m_landList)
+            {
+                m_landList.TryGetValue(parcelLocalID, out land);
+            }
+
+            if (land != null)
+            {
+                land.deedToGroup(groupID);
+            }
+
+        }
+
+
         #region Land Object From Storage Functions
 
         public void IncomingLandObjectsFromStorage(List<LandData> data)

OpenSim/Region/CoreModules/World/Land/LandObject.cs

@@ -232,6 +232,18 @@ namespace OpenSim.Region.CoreModules.World.Land
             sendLandUpdateToAvatarsOverMe();
         }
 
+        public void deedToGroup(UUID groupID)
+        {
+            LandData newData = landData.Copy();
+            newData.OwnerID = groupID;
+            newData.GroupID = groupID;
+            newData.IsGroupOwned = true;
+
+            m_scene.LandChannel.UpdateLandObject(landData.LocalID, newData);
+
+            sendLandUpdateToAvatarsOverMe();
+        }
+
         public bool isEitherBannedOrRestricted(UUID avatar)
         {
             if (isBannedFromLand(avatar))

OpenSim/Region/Framework/Interfaces/ILandObject.cs

@@ -76,6 +76,8 @@ namespace OpenSim.Region.Framework.Interfaces
         void removePrimFromCount(SceneObjectGroup obj);
         void updateLandSold(UUID avatarID, UUID groupID, bool groupOwned, uint AuctionID, int claimprice, int area);
 
+        void deedToGroup(UUID groupID);
+
         void setParcelObjectMaxOverride(overrideParcelMaxPrimCountDelegate overrideDel);
         void setSimulatorObjectMaxOverride(overrideSimulatorMaxPrimCountDelegate overrideDel);
 

OpenSim/Region/OptionalModules/Avatar/XmlRpcGroups/XmlRpcGroupsModule.cs

@@ -552,7 +552,10 @@ namespace OpenSim.Region.OptionalModules.Avatar.XmlRpcGroups
             {
                 GroupTitlesData title = new GroupTitlesData();
                 title.Name = role.Name;
-                title.Selected = agentMembership.ActiveRole == role.RoleID;
+                if (agentMembership != null)
+                {
+                    title.Selected = agentMembership.ActiveRole == role.RoleID;
+                }
                 title.UUID = role.RoleID;
             }