java.lang.NoClassDefFoundError help?

[softballfrk13608]

I've been using eclipse for all of my programming for a long time, but now when I try to run a program in the command line, I keep getting this error:

Exception in thread "main" java.lang.NoClassDefFoundError: jGamp (wrong name: org/jMath/PWA/Gamp/jGamp)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(ClassLoader. java:631)
at java.lang.ClassLoader.defineClass(ClassLoader.java :615)
at java.security.SecureClassLoader.defineClass(Secure ClassLoader.java:141)
at java.net.URLClassLoader.defineClass(URLClassLoader .java:283)
at java.net.URLClassLoader.access$000(URLClassLoader. java:58)
at java.net.URLClassLoader$1.run(URLClassLoader.java: 197)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.j ava:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:3 06)
at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:2 47)

Any help on this would be greatly appreciated!

[copeg]

Where is that class/package? It is not part of the standard JRE...is it on the classpath?

[Norm]

when I try to run a program in the command line

Can you post the full text of the command line you are using?

Do you include the full package path with the class name? Where is the class file located?