diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0488b61a3a8f2da61704564213f31328667de145..612a3bf845116f59f25eaeebb9f30b19ce979c34 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,13 +4,12 @@ project(macaon2)
 
 add_definitions("-Wall" )
 
-# for gcc < 5.3
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=gnu11")
-
-# better, but needs CMake >= 3.0
-#set_property(GLOBAL PROPERTY CXX_STANDARD 11)
-#set_property(GLOBAL PROPERTY C_STANDARD 11)
-
+if (${CMAKE_C_COMPILER_VERSION} VERSION_LESS 5.3)
+	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=gnu11")
+	# better, but needs CMake >= 3.0
+	#set_property(GLOBAL PROPERTY CXX_STANDARD 11)
+	#set_property(GLOBAL PROPERTY C_STANDARD 11)
+endif()
 
 # activate with cmake -DMACA_EXPORT=TRUE 
 # to use macaon in python/java (with swig)
diff --git a/INSTALL b/INSTALL
index f031c1e9cb5a162913d80aa8cdbc7cf557486a6c..7fe96bf8ad3a5849a7d8b5da8f2e7f2bf36b5f46 100644
--- a/INSTALL
+++ b/INSTALL
@@ -16,8 +16,15 @@ The basic procedure to build and install macaon from sources is the following.
   If you want to install macaon locally, you can specify the install path with :
     cmake -DCMAKE_INSTALL_PREFIX:PATH=/absolute/path/to/macaon_install_dir ..
 
-  If you want to create a library to use in python
+  If you want to create a library to use in python or java
     cmake -DMACA_EXPORT=TRUE ..
+  you need to install the following packages on Ubuntu
+	sudo apt-get install swig
+	sudo apt-get install libpython2.7-dev
+
+	sudo apt-get install openjdk-8-jdk 
+     or
+	sudo apt-get install openjdk-7-jdk 
 
 - Build the sources with:
     make