diff --git a/main/src/com/google/refine/operations/OperationRegistry.java b/main/src/com/google/refine/operations/OperationRegistry.java
index 6f8fcdd0b..c0598b7ca 100644
--- a/main/src/com/google/refine/operations/OperationRegistry.java
+++ b/main/src/com/google/refine/operations/OperationRegistry.java
@@ -2,6 +2,8 @@ package com.google.refine.operations;
 
 import java.lang.reflect.Method; 
 import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
 import java.util.Map;
 
 import org.json.JSONObject;
@@ -13,14 +15,23 @@ import edu.mit.simile.butterfly.ButterflyModule;
 
 public abstract class OperationRegistry {
 
-    static final public Map<String, Class<? extends AbstractOperation>> s_opNameToClass = new HashMap<String, Class<? extends AbstractOperation>>();
-    static final public Map<Class<? extends AbstractOperation>, String> s_opClassToName = new HashMap<Class<? extends AbstractOperation>, String>();
+    static final public Map<String, List<Class<? extends AbstractOperation>>> s_opNameToClass =
+        new HashMap<String, List<Class<? extends AbstractOperation>>>();
+    
+    static final public Map<Class<? extends AbstractOperation>, String> s_opClassToName =
+        new HashMap<Class<? extends AbstractOperation>, String>();
     
     static public void registerOperation(ButterflyModule module, String name, Class<? extends AbstractOperation> klass) {
         String key = module.getName() + "/" + name;
         
-        s_opNameToClass.put(key, klass);
         s_opClassToName.put(klass, key);
+        
+        List<Class<? extends AbstractOperation>> classes = s_opNameToClass.get(key);
+        if (classes == null) {
+            classes = new LinkedList<Class<? extends AbstractOperation>>();
+            s_opNameToClass.put(key, classes);
+        }
+        classes.add(klass);
     }
     
     static public AbstractOperation reconstruct(Project project, JSONObject obj) {
@@ -30,8 +41,10 @@ public abstract class OperationRegistry {
                 op = "core/" + op; // backward compatible
             }
             
-            Class<? extends AbstractOperation> klass = OperationRegistry.s_opNameToClass.get(op);
-            if (klass != null) {
+            List<Class<? extends AbstractOperation>> classes = s_opNameToClass.get(op);
+            if (classes != null && classes.size() > 0) {
+                Class<? extends AbstractOperation> klass = classes.get(classes.size() - 1);
+                
                 Method reconstruct = klass.getMethod("reconstruct", Project.class, JSONObject.class);
                 if (reconstruct != null) {
                     return (AbstractOperation) reconstruct.invoke(null, project, obj);
diff --git a/main/src/com/google/refine/operations/SaveProtographOperation.java b/main/src/com/google/refine/operations/SaveProtographOperation.java
index 3a52fa82c..5c0eaddd5 100644
--- a/main/src/com/google/refine/operations/SaveProtographOperation.java
+++ b/main/src/com/google/refine/operations/SaveProtographOperation.java
@@ -35,22 +35,20 @@ public class SaveProtographOperation extends AbstractOperation {
     
         writer.object();
         writer.key("op"); writer.value(OperationRegistry.s_opClassToName.get(this.getClass()));
-        writer.key("description"); writer.value("Save protograph");
+        writer.key("description"); writer.value(getBriefDescription());
         writer.key("protograph"); _protograph.write(writer, options);
         writer.endObject();
     }
 
-    protected String getBriefDescription(Project project) {
-        return "Save schema skeleton";
+    protected String getBriefDescription() {
+        return "Save schema alignment skeleton";
     }
 
     @Override
     protected HistoryEntry createHistoryEntry(Project project, long historyEntryID) throws Exception {
-        String description = "Save schema-alignment protograph";
-        
         Change change = new ProtographChange(_protograph);
         
-        return new HistoryEntry(historyEntryID, project, description, SaveProtographOperation.this, change);
+        return new HistoryEntry(historyEntryID, project, getBriefDescription(), SaveProtographOperation.this, change);
     }
     
     static public class ProtographChange implements Change {
diff --git a/main/webapp/modules/core/MOD-INF/controller.js b/main/webapp/modules/core/MOD-INF/controller.js
index 571ae5315..54f229a2a 100644
--- a/main/webapp/modules/core/MOD-INF/controller.js
+++ b/main/webapp/modules/core/MOD-INF/controller.js
@@ -139,7 +139,9 @@ function registerOperations() {
     OR.registerOperation(module, "recon-judge-similar-cells", Packages.com.google.refine.operations.recon.ReconJudgeSimilarCellsOperation);
     OR.registerOperation(module, "import-qa-data", Packages.com.google.refine.operations.recon.ImportQADataOperation);
     
+    // for backward compatibility
     OR.registerOperation(module, "save-protograph", Packages.com.google.refine.operations.SaveProtographOperation);
+    OR.registerOperation(module, "save-schema-alignment-skeleton", Packages.com.google.refine.operations.SaveProtographOperation);
 }
 
 /*