diff --git a/lib/build.xml b/lib/build.xml
index 066dfff7..d480d579 100644
--- a/lib/build.xml
+++ b/lib/build.xml
@@ -20,6 +20,7 @@
 	srcdir="src/"
 	destdir="build/"
 	bootclasspath="${sdk-location}/platforms/${android.version}/android.jar"
+	source="6"
 	target="6"
 	/>
     <jar