The template for all samples, project.ant.xmlsrc, has a target "libs" that copies gwt-servlet.jar and gwt-servlet-deps.jar into WEB-INF/libs directory. gwt-servlet-deps.jar sits next to gwt-servlet.jar in the distributable. The "eclipse.generate" target, which invokes WebAppCreator, then adds all jars in WEB-INF/libs to the Eclipse classpath. This is exactly how gwt-servlet.jar is included in the project.
If you create a new app and specify the arg -maven, then the generated build file will not include a line to copy gwt-servlet-deps.jar into WEB-INF/libs. http://gwt-code-reviews.appspot.com/1047802/show -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
