Is it possible to apply a font to an RCP application when the application is already running and visible?

I'v tried using the UIManager. Startup went well, but once the application is visible, no changes are made.

Code:
Enumeration keys = UIManager.getDefaults().keys();
        while (keys.hasMoreElements()) {
            Object key = keys.nextElement();
            Object value = UIManager.get(key);
            if (value instanceof FontUIResource) {
                UIManager.put(key, configuration.getFont());
            }
Also I'v tried, starting from the rootPane, apply the font to all component (using recursion), but the result doensn't apply on all of them.

Is there a solution to apply fonts at runtime?