NoClassDefFoundError thrown on MacOSX

I'm trying to run a program that uses JOGL and Java3d that I have been working on for the past few months. It didn't give me any problems until a few days ago when I tried to migrate the Java3d and JOGL files into a folder inside the project folder (I'm using Eclipse for an IDE if it's important). Now that it's out of the system library, I'm constantly getting this error thrown at me:

Exception in thread "main" java.lang.NoClassDefFoundError: javax/media/opengl/GL
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:190)
        at javax.media.j3d.Pipeline$PipelineCreator.run(Pipeline.java:73)
        at javax.media.j3d.Pipeline$PipelineCreator.run(Pipeline.java:61)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.media.j3d.Pipeline.createPipeline(Pipeline.java:90)
        at javax.media.j3d.MasterControl.loadLibraries(MasterControl.java:832)
        at javax.media.j3d.VirtualUniverse.<clinit>(VirtualUniverse.java:274)
        at javax.media.j3d.GroupRetained.<init>(GroupRetained.java:155)
        at javax.media.j3d.TransformGroupRetained.<init>(TransformGroupRetained.java:116)
        at javax.media.j3d.TransformGroup.createRetained(TransformGroup.java:114)
        at javax.media.j3d.SceneGraphObject.<init>(SceneGraphObject.java:114)
        at javax.media.j3d.Node.<init>(Node.java:172)
        at javax.media.j3d.Group.<init>(Group.java:549)
        at javax.media.j3d.TransformGroup.<init>(TransformGroup.java:87)
        at src.Project.<clinit>(Project.java:45)
        at src.ProjectPanel.<clinit>(ProjectPanel.java:8)
Caused by: java.lang.ClassNotFoundException: javax.media.opengl.GL
        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
Thanks for any help in advance.

P.S. I posted this on StackOverflow as well, so if you want to answer there and get your answer accepted, here's the link :) http://stackoverflow.com/questions/17979266/jogl-throwing-classnotfoundexception

Hi

Java3D 1.6-pre8 requires JOGL 2.0.2, please follow these instructions:
http://gouessej.wordpress.com/2012/08/01/java-3d-est-de-retour-java-3d-is-back/#installation

Edit.: Xerxes was right, it's important to uninstall the "old" version of Java3D (1.5) installed as an extension under Mac OS X, extensions are used in priority.

Thanks for your help, turns out I had a copy of the old 1.5 jars still in my system library :)