diff --git a/src/learner/evaluation-inl.hpp b/src/learner/evaluation-inl.hpp
index 50827b758..14e66c5b7 100644
--- a/src/learner/evaluation-inl.hpp
+++ b/src/learner/evaluation-inl.hpp
@@ -115,6 +115,7 @@ struct EvalCTest: public IEvaluator {
     utils::Check(preds.size() % info.labels.size() == 0,
                  "label and prediction size not match");
     size_t ngroup = preds.size() / info.labels.size() - 1;
+    ngroup = 1;
     const unsigned ndata = static_cast<unsigned>(info.labels.size());
     utils::Check(ngroup > 1, "pred size does not meet requirement");
     utils::Check(ndata == info.info.fold_index.size(), "need fold index");
@@ -208,9 +209,11 @@ struct EvalPrecisionRatio : public IEvaluator{
   }
   virtual float Eval(const std::vector<float> &preds,
                      const MetaInfo &info) const {
-    utils::Assert(preds.size() == info.labels.size(), "label size predict size not match");
+    utils::Check(info.labels.size() != 0, "label set cannot be empty");    
+    utils::Assert(preds.size() % info.labels.size() == 0,
+                  "label size predict size not match");
     std::vector< std::pair<float, unsigned> > rec;
-    for (size_t j = 0; j < preds.size(); ++j) {
+    for (size_t j = 0; j < info.labels.size(); ++j) {
       rec.push_back(std::make_pair(preds[j], static_cast<unsigned>(j)));
     }
     std::sort(rec.begin(), rec.end(), CmpFirst);
diff --git a/src/tree/param.h b/src/tree/param.h
index 52c273749..b1bfe69a3 100644
--- a/src/tree/param.h
+++ b/src/tree/param.h
@@ -244,6 +244,7 @@ struct CVGradStats : public GradStats {
   }
   /*! \brief calculate gain of the solution */
   inline double CalcGain(const TrainParam &param) const {
+    return param.CalcGain(train[0].sum_grad, train[0].sum_hess);
     double ret = 0.0;
     for (unsigned i = 0; i < vsize; ++i) {
       ret += param.CalcGain(train[i].sum_grad,
diff --git a/src/tree/updater.h b/src/tree/updater.h
index 91e9c4079..fa8605594 100644
--- a/src/tree/updater.h
+++ b/src/tree/updater.h
@@ -63,7 +63,7 @@ inline IUpdater<FMatrix>* CreateUpdater(const char *name) {
   if (!strcmp(name, "refresh")) return new TreeRefresher<FMatrix, GradStats>();
   if (!strcmp(name, "grow_colmaker")) return new ColMaker<FMatrix, GradStats>();
   if (!strcmp(name, "grow_colmaker2")) return new ColMaker<FMatrix, CVGradStats<2> >();
-  if (!strcmp(name, "grow_colmaker5")) return new ColMaker<FMatrix, CVGradStats<5> >();
+  //  if (!strcmp(name, "grow_colmaker5")) return new ColMaker<FMatrix, CVGradStats<5> >();
   utils::Error("unknown updater:%s", name);
   return NULL;
 }
diff --git a/wrapper/xgboost_wrapper.cpp b/wrapper/xgboost_wrapper.cpp
index 975d48015..3c97e4475 100644
--- a/wrapper/xgboost_wrapper.cpp
+++ b/wrapper/xgboost_wrapper.cpp
@@ -154,6 +154,9 @@ extern "C"{
       if (src.info.info.root_index.size() != 0) {
         ret.info.info.root_index.push_back(src.info.info.root_index[ridx]);
       }
+      if (src.info.info.fold_index.size() != 0) {
+        ret.info.info.fold_index.push_back(src.info.info.fold_index[ridx]);
+      }
     }
     return p_ret;
   }