3rd party .jar includes with Google App Engine

I am writing a Google App Engine app using Java that uses 3rd party libraries. I am getting a "java.lang.NoClassDefFoundError" when running the app when it hits the line with r开发者_开发问答eferences to the 3rd party library. This app works when creating a normal servlet, so I am pretty sure the code is correct.

I am developing in Eclipse.

Does the app engine not allow 3rd party libraries?

Do I need to configure the class path differently?

HELP!!

If using Eclipse, You need to copy the required jar(s) to the /WEB-INF/lib folder manually.

Please see if the library you are using will play in the google app engine or not? This link lists most third party libraries/frameworks and the issues that occur when you use different versions of them with GAE and also possible solutions if any.

The ClassNotFoundError is seen in a some instances with some libraries with GAE. for example spring-security etc.