diff -r 71e68f7ed23f -r 9eb0eb434c67 rt/emul/zip/src/main/java/org/apidesign/bck2brwsr/emul/zip/FastJar.java
--- a/rt/emul/zip/src/main/java/org/apidesign/bck2brwsr/emul/zip/FastJar.java	Sun May 11 08:10:28 2014 +0200
+++ b/rt/emul/zip/src/main/java/org/apidesign/bck2brwsr/emul/zip/FastJar.java	Tue May 13 21:14:44 2014 +0200
@@ -36,6 +36,7 @@
 import java.lang.reflect.Method;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipInputStream;
+import org.apidesign.bck2brwsr.core.Exported;
 import org.apidesign.bck2brwsr.core.JavaScriptBody;
 
 /**
@@ -185,6 +186,8 @@
             + "    }\n"
             + "}"
     )
+    
+    @Exported
     static void arraycopy(Object src, int srcBegin, Object dst, int dstBegin, int count) {
         try {
             Class<?> system = Class.forName("java.lang.System");