That's strange - as far as I understand this error, it means that it cannot find a constructor of class "javax.resource.ResourceException", which is actually part of the J2EE framework.
Do you package any JavaEE related classes/jars (e.g. "j2ee.jar") in your app?
If not: I found this post where someone had a similar problem, but not with JBoss: http://www.ibm.com/developerworks/forums/thread.jspa?messageID=13835043
Do you try to migrate an old app? If yes: maybe it helps to recompile it and reference the current JBoss 5.1 JARs to resolve e.g. the JavaEE API.
Best regards
Wolfgang