Fixes crash when mods add TreeMaps to the Configuration map, thanks AtomicStryker, PR: #282

common/net/minecraftforge/common/Configuration.java

@@ -695,6 +695,28 @@ public class Configuration
 
     private void save(BufferedWriter out) throws IOException
     {
+        //For compatiblitties sake just in case, Thanks Atomic, to be removed next MC version
+        //TO-DO: Remove next MC version
+        Object[] categoryArray = categories.values().toArray();
+        for (Object o : categoryArray)
+        {
+            if (o instanceof TreeMap)
+            {
+                TreeMap treeMap = (TreeMap)o;
+                ConfigCategory converted = new ConfigCategory(file.getName());
+                FMLLog.warning("Forge found a Treemap saved for Configuration file " + file.getName() + ", this is deprecated behaviour!");
+                
+                for (Object key : treeMap.keySet())
+                {
+                    FMLLog.warning("Converting Treemap to ConfigCategory, key: " + key + ", property value: " + ((Property)treeMap.get(key)).value);
+                    converted.set((String)key, (Property)treeMap.get(key));
+                }
+                
+                categories.values().remove(o);
+                categories.put(file.getName(), converted);
+            }
+        }
+        
         for (ConfigCategory cat : categories.values())
         {
             if (!cat.isChild())