clarify that Ant conforms to manifest standards when writing

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@805297 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/jar.html

@@ -220,7 +220,9 @@ to a value other than its default, <code>"add"</code>.</b></p>
   </tr>
   <tr>
     <td valign="top">manifestencoding</td>
-    <td valign="top">The encoding used to read the JAR manifest, when a manifest file is specified.</td>
+    <td valign="top">The encoding used to read the JAR manifest, when
+      a manifest file is specified.  The task will always use UTF-8
+      when writing the manifest.</td>
     <td valign="top" align="center">No, defaults to the platform encoding.</td>
   </tr>
   <tr>

docs/manual/CoreTasks/manifest.html

@@ -77,7 +77,9 @@ line.</p>
   </tr>
   <tr>
     <td valign="top">encoding</td>
-    <td valign="top">The encoding used to read the existing manifest when updating.</td>
+    <td valign="top">The encoding used to read the existing manifest
+      when updating.  The task will always use UTF-8 when writing the
+      manifest.</td>
     <td valign="top" align="center">No, defaults to UTF-8 encoding.</td>
   </tr>
 </table>