diff --git a/src/tests/antunit/taskdefs/optional/native2ascii-test.xml b/src/tests/antunit/taskdefs/optional/native2ascii-test.xml
index 7a30df795..1f7aa7fe1 100644
--- a/src/tests/antunit/taskdefs/optional/native2ascii-test.xml
+++ b/src/tests/antunit/taskdefs/optional/native2ascii-test.xml
@@ -65,4 +65,50 @@ public class Adapter implements Native2AsciiAdapter {
     </native2ascii>
     <au:assertLogContains text="adapter called"/>
   </target>
+
+  <target name="-setup-UTF8-To-ASCII">
+    <mkdir dir="${input}"/>
+    <mkdir dir="${output}"/>
+    <echo file="${input}/umlauts.properties" encoding="UTF-8">äöü=ÄÖÜ
+</echo>
+    <echo file="${output}/expected/umlauts.properties"
+          encoding="ASCII">\u00e4\u00f6\u00fc=\u00c4\u00d6\u00dc
+</echo>
+  </target>
+
+  <target name="testUTF8-To-ASCII" depends="-setup-UTF8-To-ASCII">
+    <native2ascii src="${input}" dest="${output}"
+                  includes="**/*.properties"/>
+    <au:assertFilesMatch actual="${output}/umlauts.properties"
+        expected="${output}/expected/umlauts.properties"/>
+  </target>
+
+  <target name="testUTF8-To-ASCII-sun" depends="-setup-UTF8-To-ASCII"
+          description="https://bz.apache.org/bugzilla/show_bug.cgi?id=59855"
+          unless="jdk1.9+">
+    <native2ascii src="${input}" dest="${output}" implementation="sun"
+                  includes="**/*.properties"/>
+    <au:assertFilesMatch actual="${output}/umlauts.properties"
+        expected="${output}/expected/umlauts.properties"/>
+  </target>
+
+  <target name="-setup-ASCII-To-UTF8">
+    <mkdir dir="${input}"/>
+    <mkdir dir="${output}"/>
+    <echo file="${input}/umlauts.properties" encoding="ASCII">\u00e4\u00f6\u00fc=\u00c4\u00d6\u00dc
+</echo>
+    <echo file="${output}/expected/umlauts.properties"
+          encoding="UTF-8">äöü=ÄÖÜ
+</echo>
+  </target>
+
+  <target name="testASCII-To-UTF8-sun" depends="-setup-ASCII-To-UTF8"
+          description="https://bz.apache.org/bugzilla/show_bug.cgi?id=59855"
+          unless="jdk1.9+">
+    <native2ascii src="${input}" dest="${output}" implementation="sun"
+                  reverse="true" includes="**/*.properties"/>
+    <au:assertFilesMatch actual="${output}/umlauts.properties"
+        expected="${output}/expected/umlauts.properties"/>
+  </target>
+
 </project>