add date header. patch from PR #7851 by Kevin Grey

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@272560 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/taskdefs/email/MimeMailer.java

@@ -61,6 +61,7 @@ import java.io.UnsupportedEncodingException;
 import java.util.Enumeration;
 import java.util.Properties;
 import java.util.Vector;
+import java.util.Date;
 import javax.activation.DataHandler;
 import javax.activation.FileDataSource;
 import javax.mail.Message;
@@ -116,6 +117,7 @@ class MimeMailer extends Mailer {
             if (subject != null) {
                 msg.setSubject(subject);
             }
+            msg.addHeader("Date", (new Date()).toString());
 
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             PrintStream out = new PrintStream(baos);

src/main/org/apache/tools/ant/taskdefs/email/PlainMailer.java

@@ -59,6 +59,8 @@ import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.util.Enumeration;
+import java.util.Date;
+
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.mail.MailMessage;
 
@@ -103,6 +105,7 @@ class PlainMailer extends Mailer {
                 mailMessage.setSubject(subject);
             }
 
+            mailMessage.setHeader("Date", (new Date()).toString());
             mailMessage.setHeader("Content-Type", message.getMimeType());
 
             PrintStream out = mailMessage.getPrintStream();