Rich Waters of Ext JS has put up a great example of using Ext JS server-side with Aptana Jaxer. Check out the example and from there get the full source code to give it a go yourself.

"We can see that Jaxer lets developers leverage the hard work which has already been spent building client-side libraries on the server-side. These simple examples show off some of the true potential of utilizing the Ext JS framework on the server-side" says Rich.

The easy to follow example shows off a very simple wrapper around an Ext.data.Store and the corresponding Jaxer server code that returns JSON to a Ext JS datagrid.