Anyone know Java Servlets?

Trying to get an assignment done for my Advanced Java and I keep getting the following exception:

javax.servlet.ServletException: Servlet execution threw an exception

root cause

java.lang.NoClassDefFoundError: entry/PhoneBookEntry
    assignment4.AddEntry.doGet(AddEntry.java:37)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

[url]http://dat.4chan.org/b/src/1152823595563.jpg[/url] for a screenshot of it.

The thing is entry.PhoneBookEntry exists, but for some stupid reason the servlet isn't finding it (note: this didn't seem to be an issue when I compiled).

Any ideas/suggestions? If you need more info just ask.

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