Bug 134266 [Wizard] Page description not set if page message already set
Since page messages such as errors and warnings used to be displayed in the same widget as the page description, code was put in place in WizardDialog#updateDescriptionMessage() to avoid setting the page description if there was already a message. As of 3.2 M6 there is a separate widget for displaying error and warning messages and so the page description should always be set.
bundles/org.eclipse.jface/src/org/eclipse/jface/wizard/WizardDialog.java
}
            return false;
        }
        return wizard.performCancel();
    }
    /**
     * Restores the enabled/disabled state of the given control.
     *
     * @param w the control
     * @param h the map (key type: <code>String</code>, element type:
     *   <code>Boolean</code>)
     * @param key the key
     * @see #saveEnableStateAndSet
     */
    private void restoreEnableState(Control w, Map h, String key) {
        if (w != null) {
            Boolean b = (Boolean) h.get(key);
            if (b != null) {
				w.setEnabled(b.booleanValue());
			}
        }
    }
    /**
     * Restores the enabled/disabled state of the wizard dialog's
     * buttons and the tree of controls for the currently showing page.
     *
     * @param state a map containing the saved state as returned by 
     *   <code>saveUIState</code>
     * @see #saveUIState
     */