diff --git a/build.xml b/build.xml
index 1151ff7ca..a3e2404cd 100644
--- a/build.xml
+++ b/build.xml
@@ -206,6 +206,10 @@
         </jacoco:report>
     </target>
 
+    <target name="extensions_test" depends="build">
+      <ant dir="extensions/" target="test" />
+    </target>
+
     <!-- ================================================================== -->
 
     <target name="prepare_jar">
diff --git a/extensions/build.xml b/extensions/build.xml
index 1b7fa19ad..c2378e31e 100644
--- a/extensions/build.xml
+++ b/extensions/build.xml
@@ -22,4 +22,9 @@
     <ant dir="gdata/" target="clean" />
     <ant dir="pc-axis/" target="clean" />
   </target>
+
+  <target name="test">
+    <echo message="Testing extensions" />
+    <ant dir="jython/" target="test" />
+  </target>
 </project>
diff --git a/extensions/jython/build.xml b/extensions/jython/build.xml
index 4b4f151b0..3c609f15e 100644
--- a/extensions/jython/build.xml
+++ b/extensions/jython/build.xml
@@ -5,8 +5,8 @@
     |  OpenRefine Extension Jython Build File    
     |                
     +-->
-    
-<project name="refine-jython" default="build" basedir=".">
+   
+<project name="refine-jython" default="build" basedir="." xmlns:jacoco="antlib:org.jacoco.ant">
 
     <property environment="env"/>
 
@@ -27,12 +27,14 @@
     </condition>
 
     <property name="fullname" value="${name}-${version}-${revision}" />
+    <property name="java_version" value="1.8"/>
     
     <property name="refine.dir" value="${basedir}/../../main" />
     <property name="refine.webinf.dir" value="${refine.dir}/webapp/WEB-INF" />
     <property name="refine.modinf.dir" value="${refine.dir}/webapp/modules/core/MOD-INF" />
     <property name="refine.classes.dir" value="${refine.webinf.dir}/classes" />
     <property name="refine.lib.dir" value="${refine.webinf.dir}/lib" />
+    <property name="refine.tests.lib.dir" value="${refine.dir}/tests/server/lib" />
     
     <property name="src.dir" value="${basedir}/src" />
     <property name="module.dir" value="${basedir}/module" />
@@ -40,6 +42,14 @@
     <property name="lib.dir" value="${modinf.dir}/lib" />
     <property name="classes.dir" value="${modinf.dir}/classes" />
 
+    <property name="extension.tests.dir" value="${basedir}/tests" />
+    <property name="tests.build.dir" value="${extension.tests.dir}/build" />
+    <property name="tests.src.dir" value="${extension.tests.dir}/src" />
+    <property name="tests.classes.dir" value="${extension.tests.dir}/classes" />
+    <property name="tests.report.dir" value="${extension.tests.dir}/report"/>
+    <property name="tests.report.html.dir" value="${tests.report.dir}/html"/>
+    <property name="tests.report.xml.path" value="${tests.report.dir}/jacoco.xml"/>
+ 
     <path id="class.path">
         <fileset dir="${lib.dir}">
             <include name="**/*.jar" />
@@ -48,7 +58,23 @@
             <include name="**/*.jar" />
         </fileset>
         <pathelement path="${refine.classes.dir}"/>
+        <pathelement path="${classes.dir}" />
     </path>
+
+    <path id="extension.tests.class.path">
+        <path refid="class.path"/>
+        <pathelement location="${tests.classes.dir}"/>
+        <pathelement location="${refine.tests.lib.dir}/testng-6.8.jar"/>
+        <fileset dir="${refine.tests.lib.dir}">
+            <include name="**/*.jar" />
+        </fileset>
+    </path>
+
+
+    <taskdef resource="testngtasks" classpath="${refine.tests.lib.dir}/testng-6.8.jar"/>
+    <taskdef uri="antlib:org.jacoco.ant" resource="org/jacoco/ant/antlib.xml">
+        <classpath path="${refine.tests.lib.dir}/jacocoant.jar"/>
+    </taskdef>
             
     <target name="build_java">
         <mkdir dir="${classes.dir}" />
@@ -60,7 +86,46 @@
 
     <target name="build" depends="build_java"/>
 
+    <target name="build_tests" depends="build">
+        <mkdir dir="${tests.classes.dir}" />
+        <javac source="${java_version}" target="${java_version}" encoding="utf-8" srcdir="${tests.src.dir}" destdir="${tests.classes.dir}" debug="true" includeAntRuntime="no">
+            <classpath refid="extension.tests.class.path" />
+        </javac>
+        <copy file="${tests.src.dir}/tests.log4j.properties" tofile="${tests.classes.dir}/tests.log4j.properties"/>
+    </target>
+ 
+    <mkdir dir="${tests.build.dir}" />
+    <target name="test" depends="build_tests">
+	<jacoco:coverage destfile="${tests.report.dir}/jacoco.exec">
+            <testng verbose="2" haltOnFailure="true" workingdir="${tests.build.dir}"
+                listener="org.testng.reporters.DotTestListener" excludedgroups="broken"
+                classpathref="extension.tests.class.path">
+             <xmlfileset file="${extension.tests.dir}/conf/tests.xml"/>
+            </testng>
+	</jacoco:coverage>
+        <jacoco:report>
+           <executiondata>
+		   <file file="${tests.report.dir}/jacoco.exec"/>
+           </executiondata>
+
+           <structure name="Jython extension">
+               <classfiles>
+		       <fileset dir="${classes.dir}"/>
+               </classfiles>
+                <sourcefiles encoding="UTF-8">
+	            <fileset dir="${src.dir}"/>
+                </sourcefiles>
+            </structure>
+	    <html destdir="${tests.report.html.dir}"/>
+	    <xml destfile="${tests.report.xml.path}"/>
+        </jacoco:report>
+    </target>
+
+
     <target name="clean">
         <delete dir="${classes.dir}" />
+        <delete dir="${tests.classes.dir}" />
+        <delete dir="${tests.report.dir}" />
+        <delete dir="${tests.build.dir}" />
     </target>
 </project>
diff --git a/extensions/jython/tests/conf/tests.xml b/extensions/jython/tests/conf/tests.xml
new file mode 100644
index 000000000..86ba31ab2
--- /dev/null
+++ b/extensions/jython/tests/conf/tests.xml
@@ -0,0 +1,14 @@
+<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd" >
+ 
+<suite name="Jython extension">
+  <test name="tests">
+    <groups>
+      <run>
+        <exclude name="broken" />
+      </run>
+    </groups>
+    <packages>
+      <package name="com.google.refine.jython.*" />
+    </packages>
+  </test>
+</suite>
diff --git a/extensions/jython/tests/com/google/refine/jython/JythonEvaluableTest.java b/extensions/jython/tests/src/com/google/refine/jython/JythonEvaluableTest.java
similarity index 100%
rename from extensions/jython/tests/com/google/refine/jython/JythonEvaluableTest.java
rename to extensions/jython/tests/src/com/google/refine/jython/JythonEvaluableTest.java
diff --git a/extensions/jython/tests/src/tests.log4j.properties b/extensions/jython/tests/src/tests.log4j.properties
new file mode 100644
index 000000000..ce3509f30
--- /dev/null
+++ b/extensions/jython/tests/src/tests.log4j.properties
@@ -0,0 +1,4 @@
+log4j.rootLogger=ERROR, console
+
+log4j.appender.console=org.apache.log4j.ConsoleAppender
+log4j.appender.console.layout=com.google.refine.logging.IndentingLayout
diff --git a/refine b/refine
index 4f0f68fa0..798152ab6 100755
--- a/refine
+++ b/refine
@@ -66,6 +66,7 @@ and <action> is one of
    test ................................ Run all OpenRefine tests
    server_test ......................... Run only the server tests
    ui_test ............................. Run only the UI tests
+   extensions_test ..................... Run only the extensions tests
 
    broker .............................. Run OpenRefine Broker
    
@@ -591,6 +592,7 @@ mac_dist() {
 test() {
     server_test $1
     ui_test $1 
+    extensions_test $1
 }
 
 ui_test() {
@@ -635,6 +637,10 @@ server_test() {
     ant server_test
 }
 
+extensions_test() {
+    ant extensions_test
+}
+
 run() {
     FORK=$1
     
@@ -1018,6 +1024,8 @@ case "$ACTION" in
   ui_tests) ui_test $1;;  
   server_test) server_test $1;;  
   server_tests) server_test $1;;  
+  extensions_test) extensions_test $1;;
+  extensions_tests) extensions_test $1;;
   findbugs) findbugs;;  
   pmd) pmd;;  
   cpd) cpd;;