--- a/build.xml
+++ b/build.xml
@@ -20,7 +20,7 @@
 	<target name="compile">
 		<delete dir="build" />
 		<mkdir dir="build" />
-		<javac target="1.7" source="1.7" srcdir="src" destdir="build" debug="on" />
+		<javac target="1.7" encoding="UTF-8" source="1.7" srcdir="src" destdir="build" debug="on" />
 		<copy file="src/net/sourceforge/plantuml/version/logo.png"
 			todir="build/net/sourceforge/plantuml/version" />
 		<copy file="src/net/sourceforge/plantuml/version/favicon.png"
