diff --git a/app/build.xml b/app/build.xml
index 246ba637d..449cf295e 100644
--- a/app/build.xml
+++ b/app/build.xml
@@ -53,7 +53,7 @@
 	   excludes="**/tools/format/**" 
 	   encoding="UTF-8"
 	   includeAntRuntime="false"
-	   classpath="../core/core.jar; lib/antlr.jar; lib/apple.jar; lib/ecj.jar; lib/jna.jar" />
+	   classpath="../core/core.jar; lib/ant.jar; lib/ant-launcher.jar; lib/antlr.jar; lib/apple.jar; lib/ecj.jar; lib/jna.jar" />
   </target>
   
   <target name="build" depends="compile" description="Build pde">