I found the dependency aws-java-sdk was being compiled on a legacy code, having as result a very heavy EAR.
I declared this dependency as provided and wanted to put it as part of the Jboss modules, but no matter where I put it, I'm still having the ClassNotFound issue.
Here is my module.xml:
<module xmlns="urn:jboss:module:1.1" name="com.amazonaws">
<properties>
<property name="jboss.api" value="private"/>
</properties>
<resources>
<resource-root path="aws-java-sdk-1.11.584.jar"/>
</resources>
<dependencies>
<module name="javax.api"/>
<module name="javax.xml.stream.api"/>
<module name="javax.xml.bind.api"/>
<module name="com.fasterxml.jackson"/>
<module name="org.joda.time"/>
</dependencies>
</module>
And the error:
Caused by: java.lang.NoClassDefFoundError: com/amazonaws/auth/AWSCredentials
The problem was on the JAR file, needed sdk-core. Check your JARs always.