diff --git a/CuckooChessEngine/build_binbook.xml b/CuckooChessEngine/build_binbook.xml
index cff808c..badb607 100644
--- a/CuckooChessEngine/build_binbook.xml
+++ b/CuckooChessEngine/build_binbook.xml
@@ -1,8 +1,11 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <project default="build_binbook" name="Build assets/eco.dat">
     <target name="build_binbook">
-        <java classpath="bin"
-              classname="chess.Book">
+        <java classname="chess.Book">
+        	<classpath>
+                <pathelement location="bin"/>
+                <pathelement location="bin/classes"/>
+        	</classpath>
             <arg value="${basedir}/src/book.txt"/>  
             <arg value="${basedir}/src/book.bin"/>
         </java>