Question: this may be a stupid question but after 30minutes of Googleing, I still havent found an answer..

I want to build the example program "gwt-beans-binding" ( <http://code.google.com/p/gwt-beans-binding/>.

I download the \*jar file and copied it into the the lib folder and added it to Properties-->Java Build Path -- >Libaries --> Add JARs.

When I'm build the project, I'm geting "java.lang.ClassNotFoundException"s...

What am I missing (do I have to write something in the \*.gwt.xml?

Answer: 
For building inside Eclipse it should be enough with adding the library jar to the Libraries. But for GWT compiling (or executing inside Developer Mode) your module file (\*.gwt.xml) has to point to the library module file. The library module file will say where the GWT source code is located.

```
<!-- this will declare where the source code is for the library GWT classes -->
<inherits name='org.gwt.beansbinding.Main' />
<!-- OR THIS... I don't really know -->
<inherits name='org.gwt.beansbinding.BeansBinding' />

```
The GWT compiler needs the sources to comile Java code to JavaScript. So you have to add the source folder to the class path too.

Can you give us the full stacktrace, what class is missing?