http://forums.sun.com/thread.jspa?threadID=709403
On how java tools find user classes:
A class/java file has a subpath name that reflects the class's fully-qualified name. For example, if the class com.mypackage.MyClass is stored under /myclasses, then /myclasses must be in the user class path and the full path to the class file must be /myclasses/com/mypackage/MyClass.class (or .java)