JDK 1.5.0 does not currently work with any version of jboss. Don't use it under any circumstances. Use a 1.4.2 version. That should be clear now.
Okay Scott, you are right!! Right after I earlier did that post, I went back and got the older version of the JDK, version 1.4.2_04 to be exact, and then after setting the env. variables correctly for it, I then tried/attempted to run JBoss and, lo and behold, it ran beautifully for me!!