diff --git a/test/com/sun/jna/CallbacksTest.java b/test/com/sun/jna/CallbacksTest.java
index 4bcc7737c3..e5b3436096 100644
--- a/test/com/sun/jna/CallbacksTest.java
+++ b/test/com/sun/jna/CallbacksTest.java
@@ -16,6 +16,7 @@
 import java.io.PrintStream;
 import java.lang.ref.Reference;
 import java.lang.ref.WeakReference;
+import java.nio.charset.Charset;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
@@ -652,8 +653,9 @@ public String callback(String arg, String arg2) {
                 return arg + arg2;
             }
         };
-        final String VALUE = "value" + UNICODE;
-        final String VALUE2 = getName() + UNICODE;
+        Charset charset = Charset.forName(Native.getDefaultStringEncoding());
+        final String VALUE = "value" + charset.decode(charset.encode(UNICODE));
+        final String VALUE2 = getName() + charset.decode(charset.encode(UNICODE));
         String value = lib.callStringCallback(cb, VALUE, VALUE2);
         assertTrue("Callback not called", called[0]);
         assertEquals("Wrong String callback argument 0", VALUE, cbargs[0]);
@@ -673,8 +675,9 @@ public String callback(String arg, String arg2) {
         Map<?, ?> m = CallbackReference.allocations;
         m.clear();
 
-        String arg = getName() + "1" + UNICODE;
-        String arg2 = getName() + "2" + UNICODE;
+        Charset charset = Charset.forName(Native.getDefaultStringEncoding());
+        String arg = getName() + "1" + charset.decode(charset.encode(UNICODE));
+        String arg2 = getName() + "2" + charset.decode(charset.encode(UNICODE));
         String value = lib.callStringCallback(cb, arg, arg2);
         WeakReference<Object> ref = new WeakReference<Object>(value);
 
@@ -723,7 +726,8 @@ public String[] callback(String[] arg) {
                 return arg;
             }
         };
-        final String VALUE = "value" + UNICODE;
+        Charset charset = Charset.forName(Native.getDefaultStringEncoding());
+        final String VALUE = "value" + charset.decode(charset.encode(UNICODE));
         final String[] VALUE_ARRAY = { VALUE, null };
         Pointer value = lib.callStringArrayCallback(cb, VALUE_ARRAY);
         assertTrue("Callback not called", called[0]);
@@ -795,7 +799,8 @@ public TestStructure.ByValue callback(TestStructure.ByValue s) {
     public void testUnionByValueCallbackArgument() throws Exception{
         TestLibrary.TestUnion arg = new TestLibrary.TestUnion();
         arg.setType(String.class);
-        final String VALUE = getName() + UNICODE;
+        Charset charset = Charset.forName(arg.getStringEncoding());
+        final String VALUE = getName() + charset.decode(charset.encode(UNICODE));
         arg.f1 = VALUE;
         final boolean[] called = { false };
         final TestLibrary.TestUnion[] cbvalue = { null };
diff --git a/test/com/sun/jna/ReturnTypesTest.java b/test/com/sun/jna/ReturnTypesTest.java
index 646ee2216e..6afbd58b9f 100644
--- a/test/com/sun/jna/ReturnTypesTest.java
+++ b/test/com/sun/jna/ReturnTypesTest.java
@@ -12,6 +12,7 @@
  */
 package com.sun.jna;
 
+import java.nio.charset.Charset;
 import java.util.Collections;
 import java.util.List;
 import junit.framework.TestCase;
@@ -314,7 +315,8 @@ public void testReturnPointerArray() {
     }
 
     public void testReturnStringArray() {
-        final String VALUE = getName() + UNICODE;
+        Charset charset = Charset.forName(Native.getDefaultStringEncoding());
+        final String VALUE = getName() + charset.decode(charset.encode(UNICODE));
         String[] input = {
             VALUE, null,
         };
diff --git a/test/com/sun/jna/StructureTest.java b/test/com/sun/jna/StructureTest.java
index f2ef9a36c0..833d057019 100644
--- a/test/com/sun/jna/StructureTest.java
+++ b/test/com/sun/jna/StructureTest.java
@@ -12,6 +12,7 @@
  */
 package com.sun.jna;
 
+import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -1084,9 +1085,10 @@ protected List<String> getFieldOrder() {
                 return Arrays.asList("inner");
             }
         }
-        final String VALUE = getName() + UNICODE;
-        final WString WVALUE = new WString(VALUE);
         StructureFromPointer o = new StructureFromPointer();
+        Charset charset = Charset.forName(o.getStringEncoding());
+        final String VALUE = getName() + charset.decode(charset.encode(UNICODE));
+        final WString WVALUE = new WString(VALUE);
         o.s = VALUE;
         o.ws = WVALUE;
         o.write();