I'm currently working on the porting of our JBoss 4.2 infrastructure to JBoss 5.x, and even maybe 6.x.
Since JBoss doesn't allow automated remote deployment (i.e., via JMX for example -a manual access to the JBoss console is necessary) of applications (WAR, EJBs, EARs, etc.), we used to call the JBoss MainDeployer's deploy method with a URL pointing to an HTTP URL which contains all our deployable artifacts.
As of JBoss 5.x, this broke. I'm attaching stack traces for JBoss 5 and JBoss 6; in JBoss 5 we clearly see that org.jboss.virtual.VFS.getVFS throws: java.io.IOException: No context factory for http://192.168.0.12:58407/simple-war-1.0.3-SNAPSHOT.war