NoSuchMethodError exception on SSLSocketImpl.receivedChangeCipherSpec when using javapns in GAE

I am using javapns with Google App Engine. Everything was working fine until this morning. Now, it raises this exception:

java.lang.NoSuchMethodError: sun.security.ssl.SSLSocketImpl.receivedChangeCipherSpec()Z
    at sun.security.ssl.Handshaker.receivedChangeCipherSpec(Handshaker.java:356)
    at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:347)
    at sun.security.ssl.Handshaker.processLoop(Handshaker.java:901)
    at sun.security.ssl.Handshaker.process_record(Handshaker.java:837)
    at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1026)
    at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1324)
    at sun.security.ssl.SSLSocketImpl.writeRecord(SSLSocketImpl.java:712)
    at sun.security.ssl.AppOutputStream.write(AppOutputStream.java:122)
    at java.io.OutputStream.write(OutputStream.java:75)
    at javapns.notification.PushNotificationManager.sendNotification(PushNotificationManager.java:402)
    at javapns.notification.PushNotificationManager.sendNotification(PushNotificationManager.java:350)
    at javapns.notification.PushNotificationManager.sendNotification(PushNotificationManager.java:320)
    at javapns.Push.sendPayload(Push.java:177)
    at javapns.Push.payload(Push.java:149)

Any idea? I have seen the missing method in JDK7u but I think I am using JDK7. Not sure if this is related.

I contacted Google Support regarding this issue and got the following response:

This is a known issue that is already resolved.

They did not disclosure the root cause.