"ren_richard" - first, please check your private messages again.
The following line in the error message that you get:
class file has wrong version 49.0, should be 48.0
Suggests that you are using classes that were compiled with JDK 5.0, and you are trying to use them with JDK 1.4. That will not work.
I see that you are using Tomcat 6.0. That version of Tomcat requires JDK 5.0 or newer. The JAR files in that version of Tomcat are compiled with JDK 5.0, so you will get into trouble if you try to use those JAR files on Java 1.4.
Use the JAR files that you get with Weblogic 8.1 to compile and run your application instead of those you get with Tomcat 6.0.