java.lang.SecurityException: sealing violation:

gwt, java

Solution

It means the package is sealed and you tried to load another jar also containing the package.

See Sealing Packages within a JAR File.

Problem

I am using GWT for my Java application. When I try to run it as web application, I get the following error: java.lang.SecurityException: sealing violation: can't seal package org.mortbay.util: already loaded I can't find anything helpful if I Google for the error. Am I missing something?

Original source