In the current AS trunk, i see that we are moving away from the build.xml and instead using the pom.xml to manage packaging of modules. For example, the ejb3/pom.xml http://anonsvn.jboss.org/repos/jbossas/trunk/ejb3/pom.xml has this:

 <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-antrun-plugin</artifactId>
        <executions>
          <execution>
            <id>create-output</id>
            <goals>
              <goal>run</goal>
            </goals>
            <phase>package</phase>
            <configuration>
              <tasks>
                                
                <mkdir dir="target/etc"/>
                <copy todir="target/etc" filtering="yes">
                  <fileset dir="src/etc">
                    <include name="**"/>
                  </fileset>
                </copy>
                
                <mkdir dir="target/resources"/>
                <copy todir="target/resources" filtering="yes">
                  <fileset dir="src/resources">
                    <include name="**"/>
                  </fileset>
                </copy>
                                
                <unjar src="${maven.dependency.org.jboss.ejb3.jboss-ejb3-core.jar.path}" dest="target/resources">
                  <patternset>
                    <include name="*.xml" />
                    <exclude name="META-INF/*.xml" />
                    <include name="META-INF/*.properties" />
                  </patternset>
                </unjar>
                
                <mkdir dir="target/ejb3.deployer"/>
                <copy todir="target/ejb3.deployer">
                   <fileset dir="target">
                      <include name="jboss-as-ejb3-deployer.jar"/>
                   </fileset>
                   <fileset dir="target/resources">
                      <include name="META-INF/ejb3-deployers-jboss-beans.xml"/>
                      <include name="META-INF/jpa-deployers-jboss-beans.xml"/>
                   </fileset>
                   <fileset dir="target/resources">
                      <include name="META-INF/persistence.properties"/>
                   </fileset>
                </copy>
                
                <copy todir="target">
                   <fileset dir="target/resources">
                      <include name="ejb3-container-jboss-beans.xml"/>
                      <include name="ejb3-connectors-jboss-beans.xml"/>
                      <include name="ejb3-interceptors-aop.xml"/>
                   </fileset>
                </copy>
                
             </tasks>
            </configuration>
          </execution>

Would it be better to just delete the ejb3/build.xml to avoid the confusion? I learnt the hard way that the build.xml was no longer being used.