Currently, a user must manually set the Timezone that they are from the Portal and portal-ext.properties. It would be helpful and convenient if Liferay could perform an automatic time change update as experienced with Windows 7 and other mobile devices without having to do to it manually. For example, if a user in Idaha observes MST during the winter and MDT during the summer, the Idaho user would have to manually change his portal display setting from MST to MDT in Spring and back again in the fall.
Some options to consider regarding this Feature Request would be: Currently, the JRE and portal code already use Java timezone IDs internally throughout. Theoretically, all that is required is some type of modification to portal-web/html/portlet/users_admin/user/display_settings.jsp to change the timezone dropdown list options to show timezone IDs to the user instead of the more limited choice of GMT offsets (MST etc.)
Another option would be to modify taglib/ui/input-timezone/page.jsp instead (without changing its tag argument interface), or provide an additional liferay-ui tag like liferay-ui:input-time but displaying the timezone IDs as option labels instead of the GMT offsets.