To debug in Eclipse, it is nice to create a simple project which depends on all your sources + JBoss build:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>yourgroup</groupId>
<artifactId>yourparent</artifactId>
<version>yourversion</version>
</parent>
<artifactId>yourapp-jboss-debug</artifactId>
<name>yourproject: JBoss Debug Project</name>
<description>yourproject: JBoss Debug Project</description>
<packaging>jar</packaging>
<!-- Dependency list -->
<dependencies>
<!-- Dependency to JBoss build which brings all jars and sources -->
<dependency>
<groupId>org.jboss.as</groupId>
<artifactId>jboss-as-build</artifactId>
<version>7.1.1.Final</version>
<type>pom</type>
</dependency>
<!-- Dependency to yourapp build which brings all jars and sources -->
<dependency>
<groupId>yourgroup</groupId>
<artifactId>yourproject which builds all the sources and gets deployed - probably the ear</artifactId>
<version>${project.version}</version>
<type>pom</type>
</dependency>
</dependencies>
</project>
Then you do "mvn clean install eclipse:eclipse -DdownloadSources=true" (of course with maven repo http://repository.jboss.org/nexus/content/groups/public configured in maven settings) and configure your debug configuration in Eclipse to run in with this project and voila, there it is, all the JBoss sources are attached!