diff --git a/build.xml b/build.xml
index 51b28241677f9b14062fe920f6c1c28435e74e90..4adb779af2ad45ee3470586324b6c7085e935168 100644
--- a/build.xml
+++ b/build.xml
@@ -51,7 +51,7 @@
   <target name="versionnumber" depends="init">
     <tstamp><format locale="fr,fr" pattern="dd/MM/yyyy" property="date"/></tstamp>
     <property name="version.major" value="4"/>
-    <property name="version.minor" value="1"/>
+    <property name="version.minor" value="2"/>
     <exec executable="svnversion" outputproperty="svn.rev" failifexecutionfails="false"/>
     <condition property="svn.revision" value="${svn.rev}" else="nosvn">
       <isset property="svn.rev"/>
diff --git a/html/relnotes.html b/html/relnotes.html
index 2f4d925fd68c4ba5dcdafdfe68335018fe177179..dec560d38892bc3f5b5c43d4f63891649aa1b758 100644
--- a/html/relnotes.html
+++ b/html/relnotes.html
@@ -59,7 +59,8 @@ The development of 4 versions continues.
 <h2>Current SVN trunk version</h2>
 
 <!--h2>Version 4.3 (): xx/xx/xxxx - Zimt</h2-->
-<!--h2>Version 4.2 (16xx): 29/05/2011 - Tring</h2-->
+
+<h2>Version 4.2 (1618): 31/05/2011 - Tring</h2>
 
 <p><ul compact="1">
 <li>Added minimal API implementation for embedded devices (android)</li>
@@ -76,7 +77,9 @@ The development of 4 versions continues.
 <li>Modified server answers so that namespaces are well placed in REST (server)</li>
 <li>Changed order of display to precision/F-measure/recall (util)</li>
 <li><span style="color: red;">Suppressed</span> incorrect computation of fallout (eval)</li>
-<li>Upgraded to <span style="color: green">OntoSim 2.1??</span> (lib)</li>
+<li>Corrected NaN derived measures when precision is 0. (eval)</li>
+<li>Set precision to 1. when alignments are empty (eval)</li>
+<li>Upgraded to <span style="color: green">OntoSim 2.2</span> (lib)</li>
 <li>Minor display changes in HTML display (server)</li>
 <li>Suppressed <tt>PreAlignment</tt> (impl)</li>
 </ul></p>
diff --git a/lib/align.jar b/lib/align.jar
index d39ba6f2275a0dddd81d4419a9e9799152552986..4cdd00125b1cdb720b75f52ee988fd65b7502d32 100644
Binary files a/lib/align.jar and b/lib/align.jar differ
diff --git a/lib/alignsvc.jar b/lib/alignsvc.jar
index ef9130c29e5e0089b7b7e1b52a75ea6a672ce8e4..f1942cf53274d1208454e51daa7bcfcb0d068ad8 100644
Binary files a/lib/alignsvc.jar and b/lib/alignsvc.jar differ
diff --git a/lib/ontowrap.jar b/lib/ontowrap.jar
index 432436c6b130226cd889ec694875bafd716e3574..d697825e5159a6e87dc98e6987063b41cbf98381 100644
Binary files a/lib/ontowrap.jar and b/lib/ontowrap.jar differ
diff --git a/lib/procalign.jar b/lib/procalign.jar
index 8f41c8a908ec7350328a718b6f37a41315650bbf..aae6af6a4cdced0dad2611567821c8c1c4615156 100644
Binary files a/lib/procalign.jar and b/lib/procalign.jar differ