diff --git a/html/relnotes.html b/html/relnotes.html
index b26459a79f7928050d9b25eb2bee09807606e077..ace02b93b447930986217038314fbd34599abb75 100644
--- a/html/relnotes.html
+++ b/html/relnotes.html
@@ -68,6 +68,8 @@ Currently the development and maintainance of 3 versions continue.
 <!--h2>Version 4.1 (1xxx): xx/09/2009 - Tring</h2-->
 
 <p><ul compact="1">
+<li>Upgraded to <span style="color: green">Pellet 2.1</span> (lib)</li>
+<li>Added tutorial 4 Pellet action (tutorial)</li>
 <li>Fixed path errors in tutorials (tutorial)</li>
 </ul></p>
 
diff --git a/html/tutorial/tutorial4/MyApp.java b/html/tutorial/tutorial4/MyApp.java
index 5d31a681b2e53ee04d367587872493d203b7eded..ae4b6442c9f6cbaabd4a462fdac7e659119d475e 100644
--- a/html/tutorial/tutorial4/MyApp.java
+++ b/html/tutorial/tutorial4/MyApp.java
@@ -134,12 +134,10 @@ public class MyApp {
 	Alignment al = null;
 	URI uri1 = null;
 	URI uri2 = null;
-	//String u1 = "http://alignapi.gforge.inria.fr/tutorial/tutorial4/ontology1.owl";
-	//String u2 = "http://alignapi.gforge.inria.fr/tutorial/tutorial4/ontology2.owl";
 	String u1 = "file:ontology1.owl";
 	String u2 = "file:ontology2.owl";
 	String method = "fr.inrialpes.exmo.align.impl.method.StringDistAlignment";
-	String tempOntoFileName = "/tmp/myresult.owl";
+	String tempOntoFileName = "results/myresult.owl";
 	Properties params = new BasicParameters();
 	try {
 	    uri1 = new URI( u1 );
@@ -255,7 +253,7 @@ public class MyApp {
 		//in = new URL("http://alignapi.gforge.inria.fr/tutorial/tutorial4/ontology1.owl").openStream();
 		//OntModelSpec.OWL_MEM_RDFS_INF or no arguments to see the difference...
 		Model model = ModelFactory.createOntologyModel(OntModelSpec.OWL_DL_MEM_RULE_INF,null);
-	    model.read(in,"file:///tmp/myresult.owl"); 
+	    model.read(in,"file:results/myresult.owl"); 
 	    in.close();
 	
 	    // Create a new query
@@ -303,7 +301,7 @@ public class MyApp {
 	//System.setErr( new PrintStream( new NullStream() ) );
 	// Load the ontology 
 	try {
-	    OWLOntology ontology = manager.loadOntology( IRI.create( "file://"+tempOntoFileName ) );
+	    OWLOntology ontology = manager.loadOntology( IRI.create( "file:"+tempOntoFileName ) );
 	    reasoner = new PelletReasoner( ontology, org.semanticweb.owlapi.reasoner.BufferingMode.NON_BUFFERING );
 	    reasoner.prepareReasoner();
 	} catch (OWLOntologyCreationException ooce) { 
@@ -315,7 +313,7 @@ public class MyApp {
 	OWLClass person = manager.getOWLDataFactory().getOWLClass( IRI.create( "http://alignapi.gforge.inria.fr/tutorial/tutorial4/ontology2.owl#Person" ) );   
 	OWLClass student = manager.getOWLDataFactory().getOWLClass( IRI.create( "http://alignapi.gforge.inria.fr/tutorial/tutorial4/ontology2.owl#Student" ) );   
 	Set<OWLNamedIndividual> instances  = reasoner.getInstances( estud, false ).getFlattened();
-	System.err.println("Pellet(Merged): There are "+instances.size()+" students "+estud.getIRI());
+	System.err.println("Pellet(Merged): There are "+instances.size()+" students "+clname(estud));
 
 	testPelletSubClass( manager, reasoner, estud, person );
 	testPelletSubClass( manager, reasoner, estud, student );
@@ -335,13 +333,17 @@ public class MyApp {
 	}
     }
 
+    private String clname( OWLClassExpression cl ) {
+	return cl.asOWLClass().getIRI().getFragment();
+    }
+
     public void testPelletSubClass( OWLOntologyManager manager, OWLReasoner reasoner, OWLClassExpression d1, OWLClassExpression d2 ) {
 	OWLAxiom axiom = manager.getOWLDataFactory().getOWLSubClassOfAxiom( d1, d2 );
 	boolean isit = reasoner.isEntailed( axiom );
 	if ( isit ) {
-	    System.out.println( "Pellet(Merged): "+d1+" is subclass of "+d2 );
+	    System.out.println( "Pellet(Merged): "+clname(d1)+" is subclass of "+clname(d2) );
 	} else {
-	    System.out.println( "Pellet(Merged): "+d1+" is not necessarily subclass of "+d2 );
+	    System.out.println( "Pellet(Merged): "+clname(d1)+" is not necessarily subclass of "+clname(d2) );
 	}
     }
 
@@ -353,9 +355,9 @@ public class MyApp {
 	    al2.addAlignCell( d1, d2, "&lt;", 1. );
 	} catch (AlignmentException ae) { ae.printStackTrace(); }
 	if ( dreasoner.isEntailed( al2 ) ) {
-	    System.out.println( "IDDL: "+d1+" <= "+d2+" is entailed" );
+	    System.out.println( "IDDL: "+clname(d1)+" <= "+clname(d2)+" is entailed" );
 	} else {
-	    System.out.println( "IDDL: "+d1+" <= "+d2+" is not entailed" );
+	    System.out.println( "IDDL: "+clname(d1)+" <= "+clname(d2)+" is not entailed" );
 	}
     }
 
diff --git a/html/tutorial/tutorial4/index.html b/html/tutorial/tutorial4/index.html
index 4a35f5a2fe7f975bf3f01291058aad35304af631..16abf7ed4b3f6c55de42a7f58d6e2d0278c88097 100644
--- a/html/tutorial/tutorial4/index.html
+++ b/html/tutorial/tutorial4/index.html
@@ -270,8 +270,8 @@ ontologies instead of the merged one.
 </p>
 <div class="button">
   <input type="button" onclick="show('qu7')" value="Show solution 1"/>
-  <!--input type="button" onclick="show('qu8')" value="Show solution 2"/>
-  <input type="button" onclick="show('qu9')" value="Show solution 3"/-->
+  <input type="button" onclick="show('qu8')" value="Show solution 2"/>
+  <!--input type="button" onclick="show('qu9')" value="Show solution 3"/-->
   <input type="button" onclick="hide('qu7');hide('qu8');hide('qu9');" value="Hide solutions"/>
 </div>
 <div class="explain" id="qu7">
@@ -396,10 +396,10 @@ IDDL: Estudiante <= Person is not entailed
 IDDL: Estudiante <= Student is entailed
 </pre>
 	
-<!--h2>Full solution</h2>
+<h2>Full solution</h2>
 	
 <p>Do you want to see a possible solution?</p>
-<p>A full working solution is <a href="MyApp.java">MyApp.java</a>.</p-->
+<p>A full working solution is <a href="MyApp.java">MyApp.java</a>.</p>
 
 <hr />
 <small>
diff --git a/html/tutorial/tutorial4/ontology1.owl b/html/tutorial/tutorial4/ontology1.owl
index e2d0a5e8102e7dedea5d43c496d63bd1acc8a9f5..0510b9ac2af11d7c4f87fc849ac0b685f4e233c9 100644
--- a/html/tutorial/tutorial4/ontology1.owl
+++ b/html/tutorial/tutorial4/ontology1.owl
@@ -39,7 +39,7 @@
     <rdfs:label xml:lang="en">Estudiante</rdfs:label>
   </owl:Class>
 
-<Estudiante>
+<Estudiante rdf:about="#Fitzgerald">
   <lastname>Fitzgerald</lastname>
   <firstname>Ella</firstname>
   <gender>Female</gender>
@@ -51,7 +51,7 @@
   <supervisor>Prof. Giancarlo Cetriolo</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Blackey">
   <lastname>Blackey</lastname>
   <firstname>Art</firstname>
   <gender>Male</gender>
@@ -64,7 +64,7 @@
   <supervisor>Pierluiggi Pomodoro</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Coleman">
   <lastname>Coleman</lastname>
   <firstname>Ornette</firstname>
   <gender>Male</gender>
@@ -76,7 +76,7 @@
   <supervisor>Carla Cipolla</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Davis">
   <lastname>Davis</lastname>
   <firstname>Miles</firstname>
   <gender>Male</gender>
@@ -88,7 +88,7 @@
   <supervisor>Univ.-Prof. Dr. Paolo Carciofo</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Coltrane">
   <lastname>Coltrane</lastname>
   <firstname>John</firstname>
   <gender>Male</gender>
@@ -98,7 +98,7 @@
   <topic>Semantic web applications, ontology management systems</topic>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Holliday">
   <lastname>Holliday</lastname>
   <firstname>Billie</firstname>
   <gender>Female</gender>
@@ -111,7 +111,7 @@
   <supervisor>Mr. Laurenzo Girafiore</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Monk">
   <lastname>Monk</lastname>
   <firstname>Thelonious</firstname>
   <gender>Male</gender>
@@ -123,7 +123,7 @@
   <supervisor>Stefano Zucchini</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#McRae">
   <lastname>McRae</lastname>
   <firstname>Carmen</firstname>
   <gender>Female</gender>
@@ -134,7 +134,7 @@
   <supervisor>Mario Staggioni</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Bley">
   <lastname>Bley</lastname>
   <firstname>Carla</firstname>
   <gender>Female</gender>
@@ -145,7 +145,7 @@
   <supervisor>Christina Melocoton</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Simone">
   <lastname>Simone</lastname>
   <firstname>Nina</firstname>
   <gender>Female</gender>
@@ -157,7 +157,7 @@
   <supervisor>Domenica Melanzana</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Joplin">
   <lastname>Joplin</lastname>
   <firstname>Janis</firstname>
   <gender>Female</gender>
@@ -170,7 +170,7 @@
   <supervisor>Fiorenta Pescadore</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Powell">
   <lastname>Powell</lastname>
   <firstname>Bud</firstname>
   <gender>Male</gender>
@@ -183,7 +183,7 @@
   <supervisor>Giovanni Dolomitti</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#DeWilde">
   <lastname>De Wilde</lastname>
   <firstname>Laurent</firstname>
   <gender>Male</gender>
@@ -195,7 +195,7 @@
   <supervisor>Simona Riccota</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Calloway">
   <lastname>Calloway</lastname>
   <firstname>Cab</firstname>
   <gender>Male</gender>
@@ -204,7 +204,7 @@
   <country>GB</country>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Goodman">
   <lastname>Goodman</lastname>
   <firstname>Benny</firstname>
   <gender>Male</gender>
@@ -216,7 +216,7 @@
   <supervisor>Prof. Dr. Riccardo Peperoni</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Parker">
   <lastname>Parker</lastname>
   <firstname>Charlie</firstname>
   <gender>Male</gender>
@@ -228,7 +228,7 @@
   <supervisor>Cecilia Parmiggiano</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Peterson">
   <lastname>Peterson</lastname>
   <firstname>Oscar</firstname>
   <gender>Male</gender>
@@ -240,7 +240,7 @@
   <supervisor>Dott. Antolio Bresaola</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Getz">
   <lastname>Getz</lastname>
   <firstname>Stan</firstname>
   <gender>Male</gender>
@@ -252,7 +252,7 @@
   <supervisor>Prof. Pierpaolo Polenta</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Zorn">
   <lastname>Zorn</lastname>
   <firstname>John</firstname>
   <gender>Male</gender>
@@ -264,7 +264,7 @@
   <supervisor>Prof. Pierpaolo Polenta</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Tyner">
   <lastname>Tyner</lastname>
   <firstname>McCoy</firstname>
   <gender>Male</gender>
@@ -276,7 +276,7 @@
   <supervisor>Dr Nanni Girasole</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Hawkins">
   <lastname>Hawkins</lastname>
   <firstname>Coleman</firstname>
   <gender>Male</gender>
@@ -288,7 +288,7 @@
   <supervisor>Pepe Frutti di Mare</supervisor>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Franklin">
   <lastname>Franklin</lastname>
   <firstname>Aretha</firstname>
   <gender>Female</gender>
@@ -297,7 +297,7 @@
   <country>ES</country>
 </Estudiante>
 
-<Estudiante>
+<Estudiante rdf:about="#Baker">
   <lastname>Baker</lastname>
   <firstname>Chet</firstname>
   <gender>Male</gender>
diff --git a/html/tutorial/tutorial4/ontology2.owl b/html/tutorial/tutorial4/ontology2.owl
index a0225623de12b698b69cdaf7e861ed22985d3251..55d4f4cc491d5ee6c038795b54cd48887ce630ff 100644
--- a/html/tutorial/tutorial4/ontology2.owl
+++ b/html/tutorial/tutorial4/ontology2.owl
@@ -43,7 +43,7 @@
     <rdfs:label xml:lang="en">Student</rdfs:label>
   </owl:Class>
 
-<Student>
+<Student rdf:about="#dkral">
   <name>Krall</name>
   <first-name>Diana</first-name>
   <gender>Female</gender>
@@ -56,7 +56,7 @@
   <phd-advisor>C. Fragola</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#dgord">
   <name>Gordon</name>
   <first-name>Dexter</first-name>
   <gender>Male</gender>
@@ -68,7 +68,7 @@
   <phd-advisor>C. Pannacotta</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#drein">
   <name>Reinhardt</name>
   <first-name>Django</first-name>
   <gender>Male</gender>
@@ -81,7 +81,7 @@
   <phd-advisor>Prof. Chr. Melocoton</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#cmill">
   <name>Miller</name>
   <first-name>Glenn</first-name>
   <gender>Male</gender>
@@ -93,7 +93,7 @@
   <phd-advisor>Professor G. Limone</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#jmcle">
   <name>McLean</name>
   <first-name>Jackie</first-name>
   <gender>Male</gender>
@@ -105,7 +105,7 @@
   <phd-advisor>S. Zucchini</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#nmerc">
   <name>Merchant</name>
   <first-name>Natalie</first-name>
   <gender>Female</gender>
@@ -115,7 +115,7 @@
   <topics-of-interest>Social Semantic Web</topics-of-interest>
 </Student>
 
-<Student>
+<Student rdf:about="#lhamp">
   <name>Hampton</name>
   <first-name>Lionel</first-name>
   <gender>Male</gender>
@@ -127,7 +127,7 @@
   <phd-advisor>O. Mascarponne</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#rjone">
   <name>Jones</name>
   <first-name>Rickie Lee</first-name>
   <gender>Female</gender>
@@ -140,7 +140,7 @@
   <phd-advisor>A. Lambretta</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#sroll">
   <name>Rollins</name>
   <first-name>Sonny</first-name>
   <gender>Male</gender>
@@ -152,7 +152,7 @@
   <phd-advisor>M. Pecorino</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#kburr">
   <name>Burrell</name>
   <first-name>Kenny</first-name>
   <gender>Male</gender>
@@ -164,7 +164,7 @@
   <phd-advisor>S. Proscuitto</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#dbrub">
   <name>Brubeck</name>
   <first-name>Dave</first-name>
   <gender>Male</gender>
@@ -177,7 +177,7 @@
   <phd-advisor>P. Tiramissu</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#delli">
   <name>Ellington</name>
   <first-name>Duke</first-name>
   <gender>Male</gender>
@@ -189,7 +189,7 @@
   <phd-advisor>Prof. G. Cetriolo</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#mjack">
   <name>Jackson</name>
   <first-name>Milt</first-name>
   <gender>Male</gender>
@@ -198,7 +198,7 @@
   <country-of-study>IT</country-of-study>
 </Student>
 
-<Student>
+<Student rdf:about="#plee">
   <name>Lee</name>
   <first-name>Peggy</first-name>
   <gender>Female</gender>
@@ -210,7 +210,7 @@
   <phd-advisor>a.Univ.Prof.DI.Dr. Z. Melone</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#agilb">
   <name>Gilberto</name>
   <first-name>Astrud</first-name>
   <gender>Female</gender>
@@ -222,7 +222,7 @@
   <phd-advisor>Pr. Dr. M. Coppa</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#erigb">
   <name>Rigby</name>
   <first-name>Eleonore</first-name>
   <gender>Female</gender>
@@ -231,7 +231,7 @@
   <country-of-study>MX</country-of-study>
 </Student>
 
-<Student>
+<Student rdf:about="#cblac">
   <name>Black</name>
   <first-name>Cilla</first-name>
   <gender>Female</gender>
@@ -242,7 +242,7 @@
   <phd-advisor>Prof. G. Limone</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#ashep">
   <name>Shepp</name>
   <first-name>Archie</first-name>
   <gender>Male</gender>
@@ -252,7 +252,7 @@
   <topics-of-interest>Personal Information Management</topics-of-interest>
 </Student>
 
-<Student>
+<Student rdf:about="#atatu">
   <name>Tatum</name>
   <first-name>Art</first-name>
   <gender>Male</gender>
@@ -264,7 +264,7 @@
   <phd-advisor>B. Tiramisu</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#ccore">
   <name>Corea</name>
   <first-name>Chick</first-name>
   <gender>Male</gender>
@@ -276,7 +276,7 @@
   <phd-advisor>Prof. Dr. A. Belladonna</phd-advisor>
 </Student>
 
-<Student>
+<Student rdf:about="#rbrya">
   <name>Bryant</name>
   <first-name>Ray</first-name>
   <institution>Handshuh University</institution>
@@ -284,7 +284,7 @@
   <country-of-study>BE</country-of-study>
 </Student>
 
-<Student>
+<Student rdf:about="#jzawi">
   <name>Zawinul</name>
   <first-name>Joe</first-name>
   <institution>Institute for Social Coworkers</institution>
@@ -292,7 +292,7 @@
   <country-of-study>ES</country-of-study>
 </Student>
 
-<Student>
+<Student rdf:about="#bsinc">
   <name>Sinclair</name>
   <first-name>Betty</first-name>
   <institution>Institute for Social Coworkers</institution>
@@ -300,7 +300,7 @@
   <country-of-study>ES</country-of-study>
 </Student>
 
-<Student>
+<Student rdf:about="#jaldde">
   <name>Aldderley</name>
   <first-name>Julian</first-name>
   <institution>Politecnico di Madalena</institution>