JBoss, sync4j and class loading

Question

Hello there, I'm in need of some help with running one webapp (sync4j) with jboss 6 I'm getting the following error: could you help me with this? I found here: https://community.jboss.org/wiki/ClassLoadingConfiguration

that i need to add this:

<jboss-app>                                                                                
    <loader-repository>
    com.example:archive=unique-archive-name
    </loader-repository>
 </jboss-app>

to my META-INF/jboss-app.xml in my EAR, but that did not help.

Also answer to this question does not help. The error still occurs.