It's pretty straightforward to setup debugging for the GWT project from Eclipse. Here are the steps below:

Install Instructions

1. Install the Eclipse GWT plugin using the appropriate update site URL:

Eclipse 3.5 (Galileo)
Detailed instructions for Eclipse 3.5

Eclipse 3.4 (Ganymede)
Detailed instructions for Eclipse 3.4

Eclipse 3.3 (Europa)
Detailed instructions for Eclipse 3.3

2. Once you have installed the plugin and restarted Eclipse, go to:

Run >> Debug Configurations

Right click on Web Application and select New to create a new Web Application Debug Configuration

3. Within this new configuration, set the "Project" as sipXconfig-gwt

4. Click on the "GWT" tab and set the browser "URL" as UserPhonebookSearch.html


More info on the Eclipse GWT Plugin

In order to output human readable Javascript, when compiling the GWT project, Inherit the debug GWT package SmartGwtDebug instead of SmartGwt in user_phonebook_search.gwt.xml.

If you need access to the SmartClient Developer Console, inherit SmartGwtTools in user_phonebook_search.gwt.xml. More info on this can be found here