diff --git a/lib/java/Makefile.am b/lib/java/Makefile.am
index ffcdc03..c5c7521 100644
--- a/lib/java/Makefile.am
+++ b/lib/java/Makefile.am
@@ -19,6 +19,8 @@
 
 EXTRA_DIST = build.xml src test
 
+export CLASSPATH
+
 all-local:
 	$(ANT) $(ANT_FLAGS)