diff --git a/.travis.yml b/.travis.yml
index e117530b4154..23377bf0f562 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -30,8 +30,6 @@ matrix:
       env: TASK=doc
     - os: linux
       env: TASK=r_test
-    - os: linux
-      env: TASK=scala_test
 
 # dependent apt packages
 addons:
diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index 38d06e5e7e07..31f1356cc0a4 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -89,3 +89,4 @@ List of Contributors
 * [Ye Zhou](https://github.com/zhouye)
 * [Zhang Chen](https://github.com/zhangchen-qinyinghua)
 * [Xianliang Wang](https://github.com/wangxianliang)
+* [Junru Shao](https://github.com/yzgysjr)
diff --git a/doc/build.md b/doc/build.md
index 95be4372ea65..8df3d9d648bf 100644
--- a/doc/build.md
+++ b/doc/build.md
@@ -126,6 +126,9 @@ various distributed filesystem such as HDFS/Amazon S3/...
 - First copy [make/config.mk](../make/config.mk) to the project root, on which
   any local modification will be ignored by git, then modify the according flags.
 
+#### Building with Intel MKL Support
+First, `source /path/to/intel/bin/compilervars.sh` to automatically set environment variables. Then, edit [make/config.mk](../make/config.mk), let `USE_BLAS = mkl`. `USE_INTEL_PATH = NONE` is usually not necessary to be modified.
+
 
 ## Python Package Installation
 
diff --git a/include/mxnet/optimizer.h b/include/mxnet/optimizer.h
index fb15f2c04ec5..5b438078519c 100644
--- a/include/mxnet/optimizer.h
+++ b/include/mxnet/optimizer.h
@@ -17,9 +17,15 @@
 #include "./base.h"
 #include "./resource.h"
 
+#if DMLC_USE_CXX11
+#include <mxnet/ndarray.h>
+#endif
+
 namespace mxnet {
 
+#if !DMLC_USE_CXX11
 class NDArray;
+#endif
 
 class Optimizer {
  public:
diff --git a/src/optimizer/sgd-inl.h b/src/optimizer/sgd-inl.h
index 8edbe337a3ae..ce1785102221 100644
--- a/src/optimizer/sgd-inl.h
+++ b/src/optimizer/sgd-inl.h
@@ -101,7 +101,6 @@ void call_sgd_update_gpu(RunContext ctx, TBlob weight, const TBlob grad,
 #endif  // MXNET_USE_CUDA
 
 #if DMLC_USE_CXX11
-#include <mxnet/ndarray.h>
 
 class SGDOpt : public Optimizer {
  public:
diff --git a/tests/travis/run_test.sh b/tests/travis/run_test.sh
index 229dda73a54a..18a55a081b8f 100755
--- a/tests/travis/run_test.sh
+++ b/tests/travis/run_test.sh
@@ -119,12 +119,17 @@ if [ ${TASK} == "scala_test" ]; then
     mkdir -p ${CACHE_PREFIX}/data
     ln -s ${CACHE_PREFIX}/data ${PWD}/data
 
+    cd scala-package
+    export JAVA_HOME=$(/usr/libexec/java_home)
+
     if [ ${TRAVIS_OS_NAME} == "osx" ]; then
-        cd scala-package
-        export JAVA_HOME=$(/usr/libexec/java_home)
         mvn clean package -P osx-x86_64
         mvn integration-test -P osx-x86_64
     fi
+    if [ ${TRAVIS_OS_NAME} == "linux" ]; then
+        mvn clean package -P linux-x86_64
+        mvn integration-test -P linux-x86_64
+    fi
 
     exit 0
 fi