add a lock on the update, this should have been there before.

still not convinced this will help, but it was wrong.

OpenSim/Data/MySQL/MySQLUserData.cs

@@ -695,10 +695,21 @@ namespace OpenSim.Data.MySQL
         }
         // override
         override public void UpdateUserAppearance(LLUUID user, AvatarAppearance appearance)
+        {
+            try
+            {
+                lock (database)
                 {
                     appearance.Owner = user;
                     database.insertAppearanceRow(appearance);
                 }
+            }
+            catch (Exception e)
+            {
+                database.Reconnect();
+                m_log.Error(e.ToString());
+            }
+        }
 
         override public void AddAttachment(LLUUID user, LLUUID item)
         {