diff --git a/build.xml b/build.xml
index 1799c9a7..9e96b41b 100644
--- a/build.xml
+++ b/build.xml
@@ -65,7 +65,7 @@
   <!-- build the java class files -->
   <target name="compile" depends="check-available,prepare">
     <javac srcdir="src/java" destdir="${classes.dir}" includeAntRuntime="false"
-           debug="on" optimize="{$build.optimize}" deprecation="on" source="1.5" target="1.5">
+           debug="on" optimize="{$build.optimize}" deprecation="on" source="1.6" target="1.5">
       <classpath refid="classpath"/>
       <exclude name="com/threerings/jme/**" unless="build.jme"/>
       <exclude name="com/threerings/openal/**" unless="build.openal"/>