NoClassDefFoundError for class XMPPTCPConnectionConfiguration on Android

Hello.

I am facing a very strange problem with smack under android.

I am getting the following error when using XMPPTCPConnectionConfiguration class:

02-24 13:06:37.347 15884-16152/com.neyper E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #3

Process: com.neyper, PID: 15884

java.lang.RuntimeException: An error occured while executing doInBackground()

at android.os.AsyncTask$3.done(AsyncTask.java:300)

at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)

at java.util.concurrent.FutureTask.setException(FutureTask.java:222)

at java.util.concurrent.FutureTask.run(FutureTask.java:242)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)

at java.lang.Thread.run(Thread.java:848)

Caused by: java.lang.NoClassDefFoundError: org.jivesoftware.smack.tcp.XMPPTCPConnectionConfiguration

at com.neyper.chat.controller.SmackConnection$CreateConnectionTask.doInBackground( SmackConnection.java:223)

at com.neyper.chat.controller.SmackConnection$CreateConnectionTask.doInBackground( SmackConnection.java:217)

at android.os.AsyncTask$2.call(AsyncTask.java:288)

at java.util.concurrent.FutureTask.run(FutureTask.java:237)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)

at java.lang.Thread.run(Thread.java:848)

I noticed this problem happens just in Android Versions below 5 (Lollipop), In version Lollipop Smack works well.

These are my dependencies:

dependencies{

compile ‘org.igniterealtime.smack:smack-android:4.1.6’

compile ‘org.igniterealtime.smack:smack-tcp:4.1.6’

compile ‘org.igniterealtime.smack:smack-android-extensions:4.1.6’

compile ‘org.igniterealtime.smack:smack-sasl-provided:4.1.6’

}

Someone could help me figuring out what is wrong. Any help will be appreciated.