Android – gmailsender does not work properly when using Proguard

I am using gmailsender to send email in my app. I follow the link below to send email in Android using JavaMail API without using the default / build in app

However, I noticed that whenever I use Proguard to build my APK, the Gmail sender does not work (when I install APK). No error is thrown, but no e-mail is sent. If I disable Proguard and generate APK, it can work normally

Anyone can suggest what might be wrong here

::: edit:: – add a small number of error messages (truncated) lines from the console and generate APK. I can avoid these warnings by ignoring them in the Proguard configuration file

[2013-07-09 10:00:38 - ] Proguard returned with error code 1. See console
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.datatransfer.DataProxy: can't find superclass or interface java.awt.datatransfer.Transferable
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.datatransfer.NativeClipboard: can't find superclass or interface java.awt.datatransfer.Clipboard
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator: can't find referenced class javax.security.sasl.Sasl
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator: can't find referenced class javax.security.sasl.Sasl
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator: can't find referenced class javax.security.sasl.SaslClient
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator: can't find 
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator$1: can't find referenced class javax.security.auth.callback.NameCallback
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator$1: can't find referenced class javax.security.sasl.RealmCallback
[2013-07-09 10:00:38 - ] Warning: com.sun.mail.imap.protocol.IMAPSaslAuthenticator$1: can't find referenced class javax.security.sasl.RealmChoiceCallback
[2013-07-09 10:00:38 - ] Warning: javax.activation.CommandInfo: can't find referenced class java.beans.Beans
[2013-07-09 10:00:38 - ] Warning: javax.activation.CommandInfo: can't find referenced class java.beans.Beans
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.ContextStorage: can't find referenced class java.awt.Toolkit
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.ContextStorage: can't find referenced class java.awt.GraphicsEnvironment
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.ContextStorage: can't find referenced class java.awt.Toolkit
[2013-07-09 10:00:38 - ] Warning: org.apache.harmony.awt.ContextStorage: can't find referenced class java.awt.Toolkit
[2013-07-09 10:00:38 - ]       You should check if you need to specify additional program jars.
[2013-07-09 10:00:38 - ] Warning: there were 247 unresolved references to classes or interfaces.
[2013-07-09 10:00:38 - ]          You may need to specify additional library jars (using '-libraryjars').
[2013-07-09 10:00:38 - ] java.io.IOException: Please correct the above warnings first.
[2013-07-09 10:00:38 - ]    at proguard.Initializer.execute(Initializer.java:321)
[2013-07-09 10:00:38 - ]    at proguard.ProGuard.initialize(ProGuard.java:211)
[2013-07-09 10:00:38 - ]    at proguard.ProGuard.execute(ProGuard.java:86)
[2013-07-09 10:00:38 - ]    at proguard.ProGuard.main(ProGuard.java:49

resolvent:

Finally, this problem is solved by updating Proguard from 4.7 to 4.9 to the latest version

Also add the following to the Proguard configuration file

-dontwarn java.awt.**
-dontwarn java.beans.Beans
-dontwarn javax.security.**
-keep class javamail.** {*;}
-keep class javax.mail.** {*;}
-keep class javax.activation.** {*;}
-keep class com.sun.mail.dsn.** {*;}
-keep class com.sun.mail.handlers.** {*;}
-keep class com.sun.mail.smtp.** {*;}
-keep class com.sun.mail.util.** {*;}
-keep class mailcap.** {*;}
-keep class mimetypes.** {*;}
-keep class myjava.awt.datatransfer.** {*;}
-keep class org.apache.harmony.awt.** {*;}
-keep class org.apache.harmony.misc.** {*;}