"Attempted duplicate class definition for name" error in JBoss EAP 5

Issue

• The following exception is thrown in the server.log while deploying two .SAR packages:

WARN  [ClassLoaderManager] Unexpected error during load of:com.example.Foo
java.lang.LinkageError: loader (instance of  org/jboss/classloader/spi/base/BaseClassLoader): attempted  duplicate class definition for name: "com/example/Foo"
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClassCond(Unknown Source)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at org.jboss.classloader.spi.base.BaseClassLoader.access$200(BaseClassLoader.java:67)
    at org.jboss.classloader.spi.base.BaseClassLoader$2.run(BaseClassLoader.java:633)
    at org.jboss.classloader.spi.base.BaseClassLoader$2.run(BaseClassLoader.java:592)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.jboss.classloader.spi.base.BaseClassLoader.loadClassLocally(BaseClassLoader.java:591)

• Does this affect only the .SARs packaging com.example.Foo class or other deployed application packages as well?