Strange problem with Google App Engine Java Mail

I'm using the MailService feature of Google App Engine in my application. It works fine in one application without any issues. But the same code doesn't work in another app. I'm not able to figure it out. Please help. Following is the piece of code that I use to send mail.

public static void sendHTMLEmail(String from, String fromName, String 
to, String toName, String subject, String body) { 
                _logger.info("entering ..."); 
                Properties props = new Properties(); 
                Session session = Session.getDefaultInstance(props, null); 
                _logger.info("got mail session ..."); 
                String htmlBody = body; 
                try { 
                        Message msg = new MimeMessage(session); 
                        _logger.info("created mimemessage ..."); 
                        msg.setFrom(new InternetAddress(from, 
                                        fromName)); 
                        _logger.info("from is set ..."); 
                        msg.addRecipient(Message.RecipientType.TO, new InternetAddress( 
                                        to, toName)); 
                        _logger.info("recipient is set ..."); 
                        msg.setSubject(subject); 
                        _logger开发者_Python百科.info("subject is set ..."); 
                        Multipart mp = new MimeMultipart(); 
                        MimeBodyPart htmlPart = new MimeBodyPart(); 
                htmlPart.setContent(htmlBody, "text/html"); 
                mp.addBodyPart(htmlPart); 
                        _logger.info("body part added ..."); 


                msg.setContent(mp); 
                        _logger.info("content is set ..."); 
                        Transport.send(msg); 
                        _logger.info("email sent successfully."); 
                } catch (AddressException e) { 
                        e.printStackTrace(); 
                } catch (MessagingException e) { 
                        e.printStackTrace(); 
                } catch (UnsupportedEncodingException e) { 
                        e.printStackTrace(); 
                } catch (Exception e) { 
                        e.printStackTrace(); 
                        System.err.println(e.getMessage()); 
                } 
        } 

When I look at the log (on the server admin console), it prints the statement "content is set ..." and after that there is nothing in the log. The mail is not sent. At times I get the following error after the above statement is printed (and the mail is not sent).

com.google.appengine.repackaged.com.google.common.base.internal.Finalizer getInheritableThreadLocalsField: Couldn't access Thread.inheritableThreadLocals. Reference finalizer threads will inherit thread local values.

But the mail quota usage keeps increasing.

Remember, this works fine in one application, but not in other. I'm using the same set of email addresses in both the apps (for from and to).

I'm really stuck with this. Appreciate any help.

Thank you. Velu

Have you tried logging the exceptions? I bet one of them is being thrown - your printStackTrace will go nowhere.