diff --git a/tools/cooja/build.xml b/tools/cooja/build.xml
index 98718093a..7606b614f 100644
--- a/tools/cooja/build.xml
+++ b/tools/cooja/build.xml
@@ -81,8 +81,8 @@ The COOJA Simulator
     </java>
   </target>
 
-  <target name="jar_all" depends="init">
-  	<ant antfile="build.xml" dir="." target="jar" inheritAll="false"/>
+  <target name="jar" depends="init">
+  	<ant antfile="build.xml" dir="." target="jar_cooja" inheritAll="false"/>
   	<ant antfile="build.xml" dir="apps/mrm" target="jar" inheritAll="false"/>
   	<ant antfile="build.xml" dir="apps/mspsim" target="jar" inheritAll="false"/>
   </target>
@@ -108,7 +108,13 @@ The COOJA Simulator
     </exec>
   </target>
 	
-  <target name="jar" depends="init, clean, compile, copy configs">
+  <target name="java_version" depends="init">
+    <exec executable="javac" dir="${build}">
+      <arg value="-version"/>
+    </exec>
+  </target>
+	
+  <target name="jar_cooja" depends="init, clean, compile, copy configs">
     <mkdir dir="${dist}"/>
     <jar destfile="${dist}/cooja.jar" basedir="${build}">
       <manifest>