In the last project, i worked, we did GWT client connected with server using RESTfull API.
So, we have completly separate server and client. It has some benefits, if for example you have an server API, which is reusable with other clients, not like GWT.
So, the main problem is how to connect GWT with Server from configuration point of view.
create some bash file, like noserver.sh
java -Xmx256M -cp "$APPDIR/src/lib/gwt-log-2.5.2.jar:$APPDIR/src:$APPDIR/bin:/usr/local/tools/gwt-linux-1.5.2/gwt-user.jar:$GWT_HOME/gwt-dev-linux.jar" com.google.gwt.dev.GWTShell -out "$APPDIR/www" -noserver -port 8080 "$@" com.example.Main/Main.html;
then you need to setup some server: jboss, tomcat, jetty to serve statically a folder
inside your gwt projects, something like www.
after you did it, run your server.
Then run the nserver.sh to run GWT.