diff --git a/build.properties b/build.properties
index a2498df5..54376951 100644
--- a/build.properties
+++ b/build.properties
@@ -15,7 +15,7 @@ test.result.dir=${target.dir}/test-results
 user.name=myui
 #java.version=1.6
 
-project.version=0.4.0
+project.version=0.4.0-1
 project.name=Hivemall
 project.groupId=hivemall
 project.organization.name=Treasure Data, Inc.
diff --git a/pom.xml b/pom.xml
index a3fa7087..0d1b9127 100644
--- a/pom.xml
+++ b/pom.xml
@@ -4,7 +4,7 @@
 
 	<groupId>io.github.myui</groupId>
 	<artifactId>hivemall</artifactId>
-	<version>0.4.0</version>
+	<version>0.4.0-1</version>
 
 	<name>Hivemall</name>
 	<description>Scalable Machine Learning Library for Apache Hive</description>
diff --git a/src/main/java/hivemall/HivemallConstants.java b/src/main/java/hivemall/HivemallConstants.java
index bab3eda9..11f33335 100644
--- a/src/main/java/hivemall/HivemallConstants.java
+++ b/src/main/java/hivemall/HivemallConstants.java
@@ -20,7 +20,7 @@
 
 public final class HivemallConstants {
 
-    public static final String VERSION = "0.4.0";
+    public static final String VERSION = "0.4.0-1";
 
     public static final String BIAS_CLAUSE = "0";
     public static final String CONFKEY_RAND_AMPLIFY_SEED = "hivemall.amplify.seed";
diff --git a/src/main/java/hivemall/fm/FMPredictUDAF.java b/src/main/java/hivemall/fm/FMPredictUDAF.java
index 70ac3428..18b7acfb 100644
--- a/src/main/java/hivemall/fm/FMPredictUDAF.java
+++ b/src/main/java/hivemall/fm/FMPredictUDAF.java
@@ -109,6 +109,11 @@ void iterate(@Nullable DoubleWritable Wj, @Nullable List<FloatWritable> Vjf, @Nu
                 if(Xj == null) {
                     throw new HiveException("Xj should not be null");
                 }
+                final int factor = Vjf.size();
+                if(factor == 0) {// workaround for TD
+                    return;
+                }
+
                 if(sumVjXj == null) {
                     int factors = Vjf.size();
                     this.sumVjXj = Arrays.asList(MutableDouble.initArray(factors, 0.d));
@@ -116,7 +121,6 @@ void iterate(@Nullable DoubleWritable Wj, @Nullable List<FloatWritable> Vjf, @Nu
                 }
 
                 final double x = Xj.get();
-                final int factor = Vjf.size();
                 if(factor < 1) {
                     throw new HiveException("# of Factor should be more than 0: " + Vjf.toString());
                 }
@@ -141,6 +145,7 @@ void merge(PartialResult other) {
                 this.sumV2X2 = other.sumV2X2;
             } else {
                 add(other.sumVjXj, sumVjXj);
+                assert (sumV2X2 != null);
                 add(other.sumV2X2, sumV2X2);
             }
         }
@@ -163,7 +168,10 @@ void merge(PartialResult other) {
             return ret;
         }
 
-        private static void add(@Nonnull final List<MutableDouble> src, @Nonnull final List<MutableDouble> dst) {
+        private static void add(@Nullable final List<MutableDouble> src, @Nonnull final List<MutableDouble> dst) {
+            if(src == null) {
+                return;
+            }
             for(int i = 0, size = src.size(); i < size; i++) {
                 MutableDouble s = src.get(i);
                 assert (s != null);
diff --git a/src/main/java/hivemall/mf/MFPredictionUDF.java b/src/main/java/hivemall/mf/MFPredictionUDF.java
index 56c65244..2f5fb226 100644
--- a/src/main/java/hivemall/mf/MFPredictionUDF.java
+++ b/src/main/java/hivemall/mf/MFPredictionUDF.java
@@ -38,12 +38,17 @@ public FloatWritable evaluate(List<Float> Pu, List<Float> Qi, double mu) throws
         if(Pu == null || Qi == null) {
             return null; //throw new HiveException("Pu should not be NULL");
         }
-        final int factor = Pu.size();
-        if(Qi.size() != factor) {
-            throw new HiveException("|Pu| " + factor + " was not equal to |Qi| " + Qi.size());
+        final int PuSize = Pu.size();
+        final int QiSize = Qi.size();
+        if(QiSize != PuSize) {
+            throw new HiveException("|Pu| " + PuSize + " was not equal to |Qi| " + QiSize);
         }
+        if(PuSize == 0) {// workaround for TD
+            return null;
+        }
+
         float ret = (float) mu;
-        for(int k = 0; k < factor; k++) {
+        for(int k = 0; k < PuSize; k++) {
             ret += Pu.get(k) * Qi.get(k);
         }
         return new FloatWritable(ret);
@@ -68,12 +73,17 @@ public FloatWritable evaluate(List<Float> Pu, List<Float> Qi, double Bu, double
             return new FloatWritable(ret);
         }
 
-        final int factor = Pu.size();
-        if(Qi.size() != factor) {
-            throw new HiveException("|Pu| " + factor + " was not equal to |Qi| " + Qi.size());
+        final int PuSize = Pu.size();
+        final int QiSize = Qi.size();
+        if(QiSize != PuSize) {
+            throw new HiveException("|Pu| " + PuSize + " was not equal to |Qi| " + QiSize);
         }
+        if(PuSize == 0) {// workaround for TD
+            return null;
+        }
+
         float ret = (float) (mu + Bu + Bi);
-        for(int k = 0; k < factor; k++) {
+        for(int k = 0; k < PuSize; k++) {
             ret += Pu.get(k) * Qi.get(k);
         }
         return new FloatWritable(ret);