--- a/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/ThreadSafetyTest.java	Sat Apr 05 19:35:30 2014 +0200
+++ b/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/ThreadSafetyTest.java	Sun Apr 06 17:46:24 2014 +0200
@@ -64,7 +64,7 @@
             executorService.submit(new Runnable() {
                 public void run() {
                     try {
-                        Object result = target.call(new TestArguments(5));
+                        Object result = target.call(new Object[]{5});
                         assertEquals(expectedResult, result);
                         ai.incrementAndGet();
                     } catch (Throwable t) {
@@ -80,14 +80,6 @@
         assertEquals(numberOfIterations, ai.get());
     }
 
-    static class TestArguments extends Arguments {
-        final int arg;
-
-        public TestArguments(int arg) {
-            this.arg = arg;
-        }
-    }
-
     static class TestRootNode extends RootNode {
 
         @Child private ValueNode child;
@@ -182,9 +174,9 @@
 
         @Override
         int execute(VirtualFrame frame) {
-            int arg = frame.getArguments(TestArguments.class).arg;
+            int arg = (Integer) frame.getArguments()[0];
             if (arg > 0) {
-                return (int) callNode.call(frame.pack(), new TestArguments(arg - 1));
+                return (int) callNode.call(new Object[]{(arg - 1)});
             } else {
                 return valueNode.execute(frame);
             }